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Interactions between Dulaglutide and Extendryl Chews

3 drug interactions and 45 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

chlorpheniramine methscopolamine

Applies to: Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine) and Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine)
Monitor

Agents with anticholinergic properties (e.g., sedating antihistamines; antispasmodics; neuroleptics; phenothiazines; skeletal muscle relaxants; tricyclic antidepressants; disopyramide) may have additive effects when used in combination. Excessive parasympatholytic effects may result in paralytic ileus, hyperthermia, heat stroke, and the anticholinergic intoxication syndrome. Peripheral symptoms of intoxication commonly include mydriasis, blurred vision, flushed face, fever, dry skin and mucous membranes, tachycardia, urinary retention, and constipation. Central symptoms may include memory loss, disorientation, incoherence, hallucinations, psychosis, delirium, hyperactivity, twitching or jerking movements, stereotypy, and seizures. Central nervous system-depressant effects may also be additively or synergistically increased when these agents are combined, especially in elderly or debilitated patients. Use of neuroleptics in combination with other neuroleptics or anticholinergic agents may increase the risk of tardive dyskinesia. In addition, some neuroleptics and tricyclic antidepressants may cause prolongation of the QT interval and theoretically, concurrent use of two or more drugs that can cause QT interval prolongation may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death.

Management

Caution is advised when agents with anticholinergic properties are combined, particularly in the elderly and those with underlying organic brain disease, who tend to be more sensitive to the central anticholinergic effects of these drugs and in whom toxicity symptoms may be easily overlooked. Patients should be advised to notify their physician promptly if they experience potential symptoms of anticholinergic intoxication such as abdominal pain, fever, heat intolerance, blurred vision, confusion, and/or hallucinations. Ambulatory patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them. A reduction in anticholinergic dosages may be necessary if excessive adverse effects develop.

References (15)
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  4. Warnes H, Lehmann HE, Ban TA (1967) "Adynamic ileus during psychoactive medication: a report of three fatal and five severe cases." Can Med Assoc J, 96, p. 1112-3
  5. Gershon S, Neubauer H, Sundland DM (1965) "Interaction between some anticholinergic agents and phenothiazines." Clin Pharmacol Ther, 6, p. 749-56
  6. Sarnquist F, Larson CP Jr (1973) "Drug-induced heat stroke." Anesthesiology, 39, p. 348-50
  7. Johnson AL, Hollister LE, Berger PA (1981) "The anticholinergic intoxication syndrome: diagnosis and treatment." J Clin Psychiatry, 42, p. 313-7
  8. Lee BS (1986) "Possibility of hyperpyrexia with antipsychotic and anticholinergic drugs." J Clin Psychiatry, 47, p. 571
  9. Forester D (1978) "Fatal drug-induced heat stroke." JACEP, 7, p. 243-4
  10. Moreau A, Jones BD, Banno V (1986) "Chronic central anticholinergic toxicity in manic depressive illness mimicking dementia." Can J Psychiatry, 31, p. 339-41
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Moderate:

phenylephrine methscopolamine

Applies to: Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine) and Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine)
Monitor

The pressor response to phenylephrine may be potentiated by the vagolytic effect of atropine, which inhibits the reflex bradycardia that would normally accompany any increases in blood pressure induced by phenylephrine. Other antimuscarinic agents may also participate in this interaction, although clinical data are lacking. In one report, pseudo-pheochromocytoma (i.e., significant increases in blood pressure and tachycardia) occurred in seven patients who underwent eye surgery and were given phenylephrine 10% ophthalmic solution and systemic atropine, three of whom subsequently developed left ventricular failure and pulmonary edema that required intensive care monitoring. Two patients had preexisting hypertension, while others had no known history of cardiovascular disease. All had received general anesthesia with propofol, phenoperidine, and vecuronium. Since phenylephrine use alone may be associated with cardiovascular toxicities including hypertension, arrhythmia, myocardial infarction and cardiac failure, the extent of involvement by atropine is uncertain. The authors reported no further cardiovascular events following implementation of various measures that reduced phenylephrine dosage and systemic exposure, including: use of a milder strength of phenylephrine ophthalmic solution; swabbing to minimize drainage into the nasolachrymal duct to the nasal mucosa; and use of a cannula to reduce drop size. In a study of six healthy volunteers, diastolic and systolic blood pressure increased by 4 mmHg following administration of phenylephrine (0.42 mcg/kg/min), compared to 17 mmHg when phenylephrine was given after three doses of atropine (0.02, 0.01 and 0.01 mg/kg at 30 minute intervals).

Management

Caution is advised if phenylephrine (systemic or ophthalmic) is used in combination with atropine or other antimuscarinic agents. Cardiovascular status, including blood pressure and heart rate, should be closely monitored. When using ophthalmic formulations, measures to minimize systemic absorption should be employed, such as digital compression of the lacrimal sac or lid closure after instillation. A milder strength (< 10%) is preferable if phenylephrine ophthalmic solution is given.

References (5)
  1. Daelman F, Andrejak M, Rajaonarivony D, Bryselbout E, Jezraoui P, Ossart M (1994) "Phenylephrine eyedrops, systemic atropine and cardiovascular adverse events." Therapie, 49, p. 467
  2. Fraunfelder FT, Fraunfelder FW; Randall JA (2001) "Drug-Induced Ocular Side Effects" Boston, MA: Butterworth-Heinemann
  3. Lai YK (1989) "Adverse effect of intraoperative phenylephrine 10%: case report." Br J Ophthalmol, 73, p. 468-9
  4. Van Der Spek AF, Hantler CB (1986) "Phenylephrine eyedrops and anesthesia." Anesthesiology, 64, p. 812-4
  5. Levine MA, Leenen FH (1992) "Role of vagal activity in the cardiovascular responses to phenylephrine in man." Br J Clin Pharmacol, 33, p. 333-6
Moderate:

phenylephrine dulaglutide

Applies to: Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine) and dulaglutide
Monitor

The efficacy of insulin and other antidiabetic agents may be diminished by certain drugs, including atypical antipsychotics, corticosteroids, diuretics, estrogens, gonadotropin-releasing hormone agonists, human growth hormone, phenothiazines, progestins, protease inhibitors, sympathomimetic amines, thyroid hormones, L-asparaginase, alpelisib, copanlisib, danazol, diazoxide, isoniazid, megestrol, omacetaxine, phenytoin, sirolimus, tagraxofusp, temsirolimus, as well as pharmacologic dosages of nicotinic acid and adrenocorticotropic agents. These drugs may interfere with blood glucose control because they can cause hyperglycemia, glucose intolerance, new-onset diabetes mellitus, and/or exacerbation of preexisting diabetes.

Management

Caution is advised when drugs that can interfere with glucose metabolism are prescribed to patients with diabetes. Close clinical monitoring of glycemic control is recommended following initiation or discontinuation of these drugs, and the dosages of concomitant antidiabetic agents adjusted as necessary. Patients should be advised to notify their physician if their blood glucose is consistently high or if they experience symptoms of severe hyperglycemia such as excessive thirst and increases in the volume or frequency of urination. Likewise, patients should be observed for hypoglycemia when these drugs are withdrawn from their therapeutic regimen.

References (87)
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  6. Goldman JA, Neri A, Ovadia J, Eckerling B, Vries A, de (1969) "Effect of chlorothiazide on intravenous glucose tolerance in pregnancy." Am J Obstet Gynecol, 105, p. 556-60
  7. Miller NR, Moses H (1978) "Transient oculomotor nerve palsy. Association with thiazide-induced glucose intolerance." JAMA, 240, p. 1887-8
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  13. Jones IG, Pickens PT (1967) "Diabetes mellitus following oral diuretics." Practitioner, 199, p. 209-10
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  18. Jori A, Carrara MC (1966) "On the mechanism of the hyperglycaemic effect of chlorpromazine." J Pharm Pharmacol, 18, p. 623-4
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  22. (2002) "Product Information. Glucotrol (glipizide)." Pfizer U.S. Pharmaceuticals
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  24. (2002) "Product Information. Synthroid (levothyroxine)." Abbott Pharmaceutical
  25. (2001) "Product Information. Carafate (sucralfate)." Hoechst Marion Roussel
  26. Stambaugh JE, Tucker DC (1974) "Effect of diphenylhydantoin on glucose tolerance in patients with hypoglycemia." Diabetes, 23, p. 679-83
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  30. Bell DS (1993) "Insulin resistance. An often unrecognized problem accompanying chronic medical disorders." Postgrad Med, 93, 99-103,
  31. Berlin I (1993) "Prazosin, diuretics, and glucose intolerance." Ann Intern Med, 119, p. 860
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  33. Haiba NA, el-Habashy MA, Said SA, Darwish EA, Abdel-Sayed WS, Nayel SE (1989) "Clinical evaluation of two monthly injectable contraceptives and their effects on some metabolic parameters." Contraception, 39, p. 619-32
  34. Virutamasen P, Wongsrichanalai C, Tangkeo P, Nitichai Y, Rienprayoon D (1986) "Metabolic effects of depot-medroxyprogesterone acetate in long-term users: a cross-sectional study." Int J Gynaecol Obstet, 24, p. 291-6
  35. Dimitriadis G, Tegos C, Golfinopoulou L, Roboti C, Raptis S (1993) "Furosemide-induced hyperglycaemia - the implication of glycolytic kinases." Horm Metab Res, 25, p. 557-9
  36. Goldman JA, Ovadia JL (1969) "The effect of estrogen on intravenous glucose tolerance in woman." Am J Obstet Gynecol, 103, p. 172-8
  37. Hannaford PC, Kay CR (1989) "Oral contraceptives and diabetes mellitus." BMJ, 299, p. 1315-6
  38. Spellacy WN, Ellingson AB, Tsibris JC (1989) "The effects of two triphasic oral contraceptives on carbohydrate metabolism in women during 1 year of use." Fertil Steril, 51, p. 71-4
  39. Ludvik B, Clodi M, Kautzky-Willer A, Capek M, Hartter E, Pacini G, Prager R (1993) "Effect of dexamethasone on insulin sensitivity, islet amyloid polypeptide and insulin secretion in humans." Diabetologia, 36, p. 84-7
  40. Domenet JG (1968) "Diabetogenic effect of oral diuretics." Br Med J, 3, p. 188
  41. Coni NK, Gordon PW, Mukherjee AP, Read PR (1974) "The effect of frusemide and ethacrynic acid on carbohydrate metabolism." Age Ageing, 3, p. 85-90
  42. Schmitz O, Hermansen K, Nielsen OH, Christensen CK, Arnfred J, Hansen HE, Mogensen CE, Orskov H, Beck-Nielsen H (1986) "Insulin action in insulin-dependent diabetics after short-term thiazide therapy." Diabetes Care, 9, p. 631-6
  43. Blayac JP, Ribes G, Buys D, Puech R, Loubatieres-Mariani MM (1981) "Effects of a new benzothiadiazine derivative, LN 5330, on insulin secretion." Arch Int Pharmacodyn Ther, 253, p. 154-63
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  52. Charan VD, Desai N, Singh AP, Choudhry VP (1993) "Diabetes mellitus and pancreatitis as a complication of L- asparaginase therapy." Indian Pediatr, 30, p. 809-10
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  56. (2001) "Product Information. Viracept (nelfinavir)." Agouron Pharma Inc
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  58. (2001) "Product Information. Oncaspar (pegaspargase)." Rhone Poulenc Rorer
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  60. (2001) "Product Information. Elspar (asparaginase)." Merck & Co., Inc
  61. (2022) "Product Information. Hyperstat (diazoxide)." Apothecon Inc
  62. (2001) "Product Information. Megace (megestrol)." Bristol-Myers Squibb
  63. Walli R, Demant T (1998) "Impaired glucose tolerance and protease inhibitors." Ann Intern Med, 129, p. 837-8
  64. (2001) "Product Information. Agenerase (amprenavir)." Glaxo Wellcome
  65. Mauss S, Wolf E, Jaeger H (1999) "Impaired glucose tolerance in HIV-positive patients receiving and those not receiving protease inhibitors." Ann Intern Med, 130, p. 162-3
  66. Kaufman MB, Simionatto C (1999) "A review of protease inhibitor-induced hyperglycemia." Pharmacotherapy, 19, p. 114-7
  67. (2001) "Product Information. Tolinase (tolazamide)." Pharmacia and Upjohn
  68. (2001) "Product Information. Orinase (tolbutamide)." Pharmacia and Upjohn
  69. (2001) "Product Information. Dymelor (acetohexamide)." Lilly, Eli and Company
  70. Wehring H, Alexander B, Perry PJ (2000) "Diabetes mellitus associated with clozapine therapy." Pharmacotherapy, 20, p. 844-7
  71. Tsiodras S, Mantzoros C, Hammer S, Samore M (2000) "Effects of protease inhibitors on hyperglycemia, hyperlipidemia, and lipodystrophy - A 5-year cohort study." Arch Intern Med, 160, p. 2050-6
  72. (2001) "Product Information. Fortovase (saquinavir)." Roche Laboratories
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  74. Hardy H, Esch LD, Morse GD (2001) "Glucose disorders associated with HIV and its drug therapy." Ann Pharmacother, 35, p. 343-51
  75. Leary WP, Reyes AJ (1984) "Drug interactions with diuretics." S Afr Med J, 65, p. 455-61
  76. (2022) "Product Information. NovoLOG Mix 70/30 (insulin aspart-insulin aspart protamine)." Novo Nordisk Pharmaceuticals Inc
  77. (2003) "Product Information. Reyataz (atazanavir)." Bristol-Myers Squibb
  78. (2003) "Product Information. Lexiva (fosamprenavir)." GlaxoSmithKline
  79. (2004) "Product Information. Apidra (insulin glulisine)." Aventis Pharmaceuticals
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  81. (2006) "Product Information. Zolinza (vorinostat)." Merck & Co., Inc
  82. (2007) "Product Information. Torisel (temsirolimus)." Wyeth-Ayerst Laboratories
  83. (2015) "Product Information. Rexulti (brexpiprazole)." Otsuka America Pharmaceutical, Inc.
  84. (2019) "Product Information. Elzonris (tagraxofusp)." Stemline Therapeutics
  85. (2019) "Product Information. Piqray (alpelisib)." Novartis Pharmaceuticals
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  87. (2026) "Product Information. Awiqli FlexTouch (insulin icodec)." Novo Nordisk Pharmaceuticals Inc

Food/lifestyle interactions

Moderate food/lifestyle interactions

Moderate:

chlorpheniramine Food/Lifestyle

Applies to: Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine)
Generally avoid

Alcohol may potentiate some of the pharmacologic effects of CNS-active agents. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.

Management

Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.

References (4)
  1. Warrington SJ, Ankier SI, Turner P (1986) "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology, 15, p. 31-7
  2. Gilman AG, eds., Nies AS, Rall TW, Taylor P (1990) "Goodman and Gilman's the Pharmacological Basis of Therapeutics." New York, NY: Pergamon Press Inc.
  3. (2012) "Product Information. Fycompa (perampanel)." Eisai Inc
  4. (2015) "Product Information. Rexulti (brexpiprazole)." Otsuka America Pharmaceutical, Inc.
Moderate:

dulaglutide Food/Lifestyle

Applies to: dulaglutide
Monitor

Glucagon-like peptide-1 (GLP-1) receptor agonists and dual GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptor agonists can delay gastric emptying, which may impact the absorption of concomitantly administered oral medications. Mild to moderate decreases in plasma concentrations of coadministered drugs have been demonstrated in pharmacokinetic studies for some GLP-1 receptor agonists (e.g., exenatide, lixisenatide), but not others. According to the prescribing information, liraglutide did not affect the absorption of several orally administered drugs to any clinically significant extent, including acetaminophen, atorvastatin, digoxin, griseofulvin, lisinopril, and an oral contraceptive containing ethinyl estradiol-levonorgestrel. Likewise, no clinically relevant effect on absorption was observed for concomitantly administered oral drugs studied with albiglutide (digoxin, ethinyl estradiol-norethindrone, simvastatin, warfarin), dulaglutide (acetaminophen, atorvastatin, digoxin, ethinyl estradiol-norelgestromin, lisinopril, metformin, metoprolol, sitagliptin, warfarin), or semaglutide (atorvastatin, digoxin, ethinyl estradiol-levonorgestrel, metformin, warfarin). The impact of dual GLP-1 and GIP receptor agonist tirzepatide on gastric emptying was reported to be dose- and time-dependent, with the greatest effect observed after a single 5 mg dose but diminished after subsequent doses. When acetaminophen was administered following a single 5 mg dose of tirzepatide, acetaminophen peak plasma concentration (Cmax) was decreased by 50% and its median time to peak plasma concentration (Tmax) delayed by 1 hour. However, no significant impact on acetaminophen Cmax and Tmax was observed after 4 consecutive weekly doses of tirzepatide (5 mg/5 mg/8 mg/10 mg), and the overall exposure (AUC) of acetaminophen was unaffected. Tirzepatide at lower doses of 0.5 mg and 1.5 mg also had minimal effects on acetaminophen exposure.

Management

Although no specific dosage adjustment of concomitant medications is generally recommended based on available data, potential clinical impact on some oral medications cannot be ruled out, particularly those with a narrow therapeutic index or low bioavailability, those that depend on threshold concentrations for efficacy (e.g., antibiotics), and those that require rapid gastrointestinal absorption (e.g., hypnotics, analgesics). Pharmacologic response to concomitantly administered oral medications should be monitored more closely following initiation, dose adjustment, or discontinuation of a GLP-1 receptor agonist or a dual GLP-1 and GIP receptor agonist.

References (9)
  1. (2005) "Product Information. Byetta (exenatide)." Amylin Pharmaceuticals Inc
  2. (2010) "Product Information. Victoza (liraglutide)." Novo Nordisk Pharmaceuticals Inc
  3. (2014) "Product Information. Tanzeum (albiglutide)." GlaxoSmithKline
  4. (2014) "Product Information. Trulicity (dulaglutide)." Eli Lilly and Company
  5. (2016) "Product Information. Adlyxin (lixisenatide)." sanofi-aventis
  6. (2022) "Product Information. Ozempic (1 mg dose) (semaglutide)." Novo Nordisk Pharmaceuticals Inc
  7. (2023) "Product Information. Mounjaro (tirzepatide)." Eli Lilly and Company Ltd
  8. (2023) "Product Information. Mounjaro (tirzepatide)." Lilly, Eli and Company
  9. Eli Lilly Canada Inc. (2023) Product monograph including patient medication information MOUNJARO tirzepatide injection. https://pdf.hres.ca/dpd_pm/00068421.PDF
Moderate:

methscopolamine Alcohol (Ethanol)

Applies to: Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine)
Generally avoid

Use of anticholinergic agents with alcohol may result in sufficient impairment of attention so as to render driving and operating machinery more hazardous. In addition, the potential for abuse may be increased with the combination. The mechanism of interaction is not established but may involve additive depressant effects on the central nervous system. No effect of oral propantheline or atropine on blood alcohol levels was observed in healthy volunteers when administered before ingestion of a standard ethanol load. However, one study found impairment of attention in subjects given atropine 0.5 mg or glycopyrrolate 1 mg in combination with alcohol.

Management

Alcohol should generally be avoided during therapy with anticholinergic agents. Patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them.

References (1)
  1. Linnoila M (1973) "Drug effects on psychomotor skills related to driving: interaction of atropine, glycopyrrhonium and alcohol." Eur J Clin Pharmacol, 6, p. 107-12
Moderate:

phenylephrine Caffeine

Applies to: Extendryl Chews (chlorpheniramine / methscopolamine / phenylephrine)
Monitor

Coadministration of two or more sympathomimetic or noradrenergic agents may increase the risk of nervousness, irritability, tachycardia, and/or increased blood pressure. Central nervous system (CNS) stimulants, particularly amphetamines, can potentiate the adrenergic response to vasopressors and other sympathomimetic and/or noradrenergic agents, including norepinephrine transporter inhibitors. Additive increases in blood pressure and heart rate may occur due to enhanced peripheral sympathetic activity.

Management

Caution is advised if two or more sympathomimetic or noradrenergic agents are coadministered. Pulse and blood pressure should be closely monitored. Consultation with individual product labeling, as well as relevant institutional protocols, may be advisable for further guidance.

References (20)
  1. Rosenblatt JE, Lake CR, van Kammen DP, Ziegler MG, Bunney WE Jr (1979) "Interactions of amphetamine, pimozide, and lithium on plasma norepineophrine and dopamine-beta-hydroxylase in schizophrenic patients." Psychiatry Res, 1, p. 45-52
  2. Cavanaugh JH, Griffith JD, Oates JA (1970) "Effect of amphetamine on the pressor response to tyramine: formation of p-hydroxynorephedrine from amphetamine in man." Clin Pharmacol Ther, 11, p. 656
  3. (2001) "Product Information. Adderall (amphetamine-dextroamphetamine)." Shire Richwood Pharmaceutical Company Inc
  4. (2001) "Product Information. Tenuate (diethylpropion)." Aventis Pharmaceuticals
  5. (2001) "Product Information. Sanorex (mazindol)." Novartis Pharmaceuticals
  6. (2001) "Product Information. Focalin (dexmethylphenidate)." Mikart Inc
  7. (2024) "Product Information. Ephedrine (ephedrine)." Hameln Pharma Ltd
  8. (2023) "Product Information. Ephedrine Hydrochloride (ephedrine)." Wockhardt UK Ltd
  9. (2026) "Product Information. Strattera (atomoxetine)." Lilly, Eli and Company
  10. (2025) "Product Information. Atomoxetine (atomoxetine)." Zentiva Pharma UK Ltd
  11. (2026) "Product Information. Atomoxetine (Apo) (atomoxetine)." Arrotex Pharmaceuticals Pty Ltd
  12. Angita Pharma, Inc (2026) AG-ATOMOXETINE Product Monograph (Health Canada) https://pdf.hres.ca/dpd_pm/00059014.PDF
  13. (2026) "Product Information. Boots Decongestant (Pseudoephedrine) (pseudoephedrine)." The Boots Company Plc
  14. (2023) "Product Information. Sinus and Nasal Decongestant (Trust) (pseudoephedrine)." Noumed Pharmaceuticals Pty Ltd
  15. (2019) "Product Information. Ephedrine (ephedrine)." Pfizer Australia Pty Ltd
  16. (2024) "Product Information. EPHEDrine Sulfate (ePHEDrine)." Amneal Pharmaceuticals LLC
  17. (2024) "Product Information. Lemsip Cough Max for Mucus Cough and Cold (guaifenesin/paracetamol/phenylephrine)." Reckitt Benckiser Healthcare (UK) Ltd
  18. emc (2026) Product information: sudafed plus blocked nose 1mg/50mg/ml nasal spray. https://www.medicines.org.uk/emc/product/14256/smpc?utm_source=chatgpt.com
  19. (2023) "Product Information. EPHEDrine Sulfate (ePHEDrine)." Baxter Corporation
  20. Neo Health (OTC) Pty Ltd (2026) Product information: pseudoephedrine hydrochloride-paracetamol capsules. https://www.ebs.tga.gov.au/ebs/picmi/picmirepository.nsf/pdf?OpenAgent&id=CP-2024-PI-02603-1&d=20260804172310101&d=20260827172310101

Disease interactions

41 potential interactions Applies to: 30 conditions, including High Blood Pressure, GERD, Asthma, Benign Prostatic Hyperplasia, and COPD.

Arrhythmia

Moderate:

Extendryl Chews

The methscopolamine in Extendryl Chews has a moderate potential interaction with Arrhythmia.

Anticholinergics block vagal inhibition of the SA nodal pacemaker. Therapy with anticholinergics should be administered cautiously in patients with tachycardia, congestive heart failure, or coronary artery disease. Premature ventricular depolarization or ventricular tachycardia or fibrillation associated with anticholinergics is rare.

Moderate:

Extendryl Chews

The methscopolamine in Extendryl Chews has a moderate potential interaction with Arrhythmia.

Antimuscarinic agents block vagal inhibition of the SA nodal pacemaker. These agents should be administered cautiously in patients with tachycardia, congestive heart failure, or coronary artery disease. Premature ventricular depolarization or ventricular tachycardia or fibrillation associated with antimuscarinic drugs is rare.

Asthma

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Asthma.

The use of systemic anticholinergics is contraindicated in the treatment of lower respiratory tract symptoms including asthma. Muscarinic receptor antagonists reduce bronchial secretions, which can result in decreased fluidity and increased thickening of secretions. However, ipratropium does not produce these effects and can be used safely in treating asthma.

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Asthma.

It has been suggested that the anticholinergic effect of antihistamines may reduce the volume and cause thickening of bronchial secretions, resulting in obstruction of respiratory tract. Some manufacturers and clinicians recommend that therapy with antihistamines be administered cautiously in patients with asthma or chronic obstructive pulmonary disease.

Autonomic Neuropathy

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Autonomic Neuropathy.

Agents with anticholinergic activity can exacerbate many of the manifestations of autonomic neuropathy, including tachycardia, anhidrosis, bladder atony, obstipation, dry mouth and eyes, cycloplegia and blurring of vision, and sexual impotence in males. Therapy with antimuscarinic agents and higher dosages of antispasmodic agents (e.g., dicyclomine or oxybutynin) should be administered cautiously in patients with autonomic neuropathy.

Benign Prostatic Hyperplasia

Moderate:

Extendryl Chews

The phenylephrine in Extendryl Chews has a moderate potential interaction with Benign Prostatic Hyperplasia.

Sympathomimetic agents may cause or worsen urinary difficulty in patients with prostate enlargement due to smooth muscle contraction in the bladder neck via stimulation of alpha-1 adrenergic receptors. Therapy with sympathomimetic agents should be administered cautiously in patients with hypertrophy or neoplasm of the prostate.

Bleeding Disorder

Moderate:

Extendryl Chews

The methscopolamine in Extendryl Chews has a moderate potential interaction with Bleeding Disorder.

Antimuscarinic agents may cause a delay in gastric emptying and possibly antral stasis in patients with gastric ulcer. Therapy with antimuscarinic agents should be administered cautiously to patients with gastric ulcer.

Cardiovascular Conditions and Disorders

Major:

Extendryl Chews

The phenylephrine in Extendryl Chews has a major potential interaction with Cardiovascular Conditions and Disorders.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Cardiovascular Conditions and Disorders.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Moderate:

Extendryl Chews

The methscopolamine in Extendryl Chews has a moderate potential interaction with Cardiovascular Conditions and Disorders.

Anticholinergics block vagal inhibition of the SA nodal pacemaker. Therapy with anticholinergics should be administered cautiously to patients with tachycardia, congestive heart failure, or coronary artery disease. Premature ventricular depolarization, ventricular tachycardia, and fibrillation associated with anticholinergics are rare.

Cerebrovascular Insufficiency

Major:

Extendryl Chews

The phenylephrine in Extendryl Chews has a major potential interaction with Cerebrovascular Insufficiency.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

COPD

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with COPD.

It has been suggested that the anticholinergic effect of antihistamines may reduce the volume and cause thickening of bronchial secretions, resulting in obstruction of respiratory tract. Some manufacturers and clinicians recommend that therapy with antihistamines be administered cautiously in patients with asthma or chronic obstructive pulmonary disease.

Diabetes Mellitus

Moderate:

Extendryl Chews

The phenylephrine in Extendryl Chews has a moderate potential interaction with Diabetes Mellitus.

Sympathomimetic agents may cause increases in blood glucose concentrations. These effects are usually transient and slight but may be significant with dosages higher than those normally recommended. Therapy with sympathomimetic agents should be administered cautiously in patients with diabetes mellitus. Closer monitoring of blood glucose concentrations may be appropriate.

Diarrhea

Minor:

Extendryl Chews

The methscopolamine in Extendryl Chews has a minor potential interaction with Diarrhea.

Diarrhea may be a symptom of incomplete intestinal obstruction, especially in patients with ileostomy or colostomy. Antimuscarinic agents may further aggravate the diarrhea. Therefore, these drugs should be administered cautiously in patients with diarrhea.

Esophageal Obstruction

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Esophageal Obstruction.

Anticholinergics are contraindicated in patients with obstructive diseases such as achalasia, esophageal stricture or stenosis, pyloroduodenal stenosis, stenosing peptic ulcer, pyloric obstruction, and paralytic ileus. Anticholinergics may further suppress intestinal motility with resultant precipitation or aggravation of toxic megacolon.

Fever

Minor:

Extendryl Chews

The methscopolamine in Extendryl Chews has a minor potential interaction with Fever.

Atropine-like agents may increase the risk of hyperthermia in patients with fever by producing anhidrosis. Therapy with atropine-like agents should be administered cautiously in febrile patients.

Gastrointestinal Obstruction

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Gastrointestinal Obstruction.

Anticholinergics are contraindicated in patients with obstructive diseases such as achalasia, esophageal stricture or stenosis, pyloroduodenal stenosis, stenosing peptic ulcer, pyloric obstruction, and paralytic ileus. Anticholinergics may further suppress intestinal motility with resultant precipitation or aggravation of toxic megacolon.

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Gastrointestinal Obstruction.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

Gastroparesis

Major:

dulaglutide

Dulaglutide has a major potential interaction with Gastroparesis.

Dulaglutide slows gastric emptying and has not been studied in patients with gastroparesis, therefore it is not recommended in these patients.

GERD

Moderate:

Extendryl Chews

The methscopolamine in Extendryl Chews has a moderate potential interaction with GERD.

Antimuscarinic agents decrease gastric motility and relax the lower esophageal sphincter which promotes gastric retention and can aggravate reflux. These drugs should be administered cautiously in patients with gastroesophageal reflux or hiatal hernia associated with reflux esophagitis.

Glaucoma/Intraocular Hypertension

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Glaucoma/Intraocular Hypertension.

Anticholinergic agents are contraindicated in patients with primary glaucoma, a tendency toward glaucoma (narrow anterior chamber angle), or adhesions (synechiae) between the iris and lens, as well as for the elderly and others in whom undiagnosed glaucoma or excessive pressure in the eye may be present. Because anticholinergics cause mydriasis, they may exacerbate these conditions.

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

Moderate:

Extendryl Chews

The phenylephrine in Extendryl Chews has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

Sympathomimetic agents can induce transient mydriasis via stimulation of alpha-1 adrenergic receptors. In patients with anatomically narrow angles or narrow-angle glaucoma, pupillary dilation can provoke an acute attack. In patients with other forms of glaucoma, mydriasis may occasionally increase intraocular pressure. Therapy with sympathomimetic agents should be administered cautiously in patients with or predisposed to glaucoma, particularly narrow-angle glaucoma.

High Blood Pressure

Minor:

Extendryl Chews

The methscopolamine in Extendryl Chews has a minor potential interaction with High Blood Pressure.

Cardiovascular effects of anticholinergics may exacerbate hypertension. Therapy with anticholinergic agents should be administered cautiously in patients with hypertension.

Hyperthyroidism

Major:

Extendryl Chews

The phenylephrine in Extendryl Chews has a major potential interaction with Hyperthyroidism.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Hyperthyroidism.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Minor:

Extendryl Chews

The methscopolamine in Extendryl Chews has a minor potential interaction with Hyperthyroidism.

In general, agents with anticholinergic activity may exacerbate hyperthyroidism. Therapy with anticholinergics should be administered cautiously in patients with hyperthyroidism. Thyroid levels should be monitored if usage is prolonged.

Hypotension

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Hypotension.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Infectious Gastroenteritis

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Infectious Gastroenteritis.

The use of drugs with antiperistaltic activity (primarily antidiarrheal and antimuscarinic agents, but also antispasmodic agents such as dicyclomine or oxybutynin at high dosages) is contraindicated in patients with diarrhea due to pseudomembranous enterocolitis or enterotoxin-producing bacteria. These drugs may prolong and/or worsen diarrhea associated with organisms that invade the intestinal mucosa, such as toxigenic E. coli, Salmonella and Shigella, and pseudomembranous colitis due to broad-spectrum antibiotics. Other symptoms and complications such as fever, shedding of organisms and extraintestinal illness may also be increased or prolonged. In general, because antiperistaltic agents decrease gastrointestinal motility, they may delay the excretion of infective gastroenteric organisms or toxins and should be used cautiously in patients with any infectious diarrhea, particularly if accompanied by high fever or pus or blood in the stool. Some cough and cold and other combination products may occasionally include antimuscarinic agents for their drying effects and may, therefore, require careful selection when necessary.

Ischemic Heart Disease

Moderate:

Extendryl Chews

The methscopolamine in Extendryl Chews has a moderate potential interaction with Ischemic Heart Disease.

Antimuscarinic agents block vagal inhibition of the SA nodal pacemaker. These agents should be administered cautiously in patients with tachycardia, congestive heart failure, or coronary artery disease. Premature ventricular depolarization or ventricular tachycardia or fibrillation associated with antimuscarinic drugs is rare.

Liver Disease

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Liver Disease.

Limited pharmacokinetic data are available for the older, first-generation antihistamines. Many appear to be primarily metabolized by the liver, and both parent drugs and metabolites are excreted in the urine. Patients with renal and/or liver disease may be at greater risk for adverse effects from antihistamines due to drug and metabolite accumulation. Therapy with antihistamines should be administered cautiously in such patients. Lower initial dosages may be appropriate.

Multiple Endocrine Neoplasia Type II

Major:

dulaglutide

Dulaglutide has a major potential interaction with Multiple Endocrine Neoplasia Type II.

GLP-1 receptor agonist antidiabetic drugs are contraindicated in patients with a personal or family history of medullary thyroid carcinoma and in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN2). Carcinogenicity studies in rodents and limited postmarketing data suggest that GLP-1 inhibitors may cause a dose-related and treatment duration-related increase in risk of thyroid C-cell tumors, although a causal relationship has not been established.

Myasthenia Gravis

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Myasthenia Gravis.

Because antimuscarinic agents have anticholinergic effects, they are contraindicated in patients with myasthenia gravis. Their use may be appropriate to reduce adverse muscarinic effects caused by an anticholinesterase agent.

Pancreatitis

Major:

dulaglutide

Dulaglutide has a major potential interaction with Pancreatitis.

The use of GLP-1 receptor agonists has been associated with rare reports of acute pancreatitis. Other antidiabetic therapies should be considered in patients with a previous history of pancreatitis, although it is not known if they are at increased risk. Patients receiving treatment with GLP-1 receptor agonists should be observed carefully for signs and symptoms of pancreatitis. If this diagnosis is suspected, the treatment should be discontinued immediately and appropriate management should be initiated. Treatment with GLP-1 receptor agonists should be permanently discontinued if pancreatitis is confirmed.

Pheochromocytoma

Major:

Extendryl Chews

The phenylephrine in Extendryl Chews has a major potential interaction with Pheochromocytoma.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

Prostate Tumor, Benign

Moderate:

Extendryl Chews

The phenylephrine in Extendryl Chews has a moderate potential interaction with Prostate Tumor, Benign.

Sympathomimetic agents may cause or worsen urinary difficulty in patients with prostate enlargement due to smooth muscle contraction in the bladder neck via stimulation of alpha-1 adrenergic receptors. Therapy with sympathomimetic agents should be administered cautiously in patients with hypertrophy or neoplasm of the prostate.

Renal Dysfunction

Moderate:

dulaglutide

Dulaglutide has a moderate potential interaction with Renal Dysfunction.

There have been reports of acute renal failure and worsening of chronic renal failure sometimes requiring hemodialysis in patients treated with GLP-1 receptor inhibitors. Some of these events occurred in patients without known underlying renal disease. These drugs should be used with caution in patients with renal impairment, especially during treatment initiation or dose escalation. Patients should be monitored, especially if they report severe gastrointestinal reactions such as nausea, vomiting, diarrhea, or dehydration. The frequency of gastrointestinal events is increased as renal function declines. There is limited clinical experience with most of these drugs in patients with severe renal impairment.

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Renal Dysfunction.

Limited pharmacokinetic data are available for the older, first-generation antihistamines. Many appear to be primarily metabolized by the liver, and both parent drugs and metabolites are excreted in the urine. Patients with renal and/or liver disease may be at greater risk for adverse effects from antihistamines due to drug and metabolite accumulation. Therapy with antihistamines should be administered cautiously in such patients. Lower initial dosages may be appropriate.

Ulcerative Colitis

Moderate:

Extendryl Chews

The methscopolamine in Extendryl Chews has a moderate potential interaction with Ulcerative Colitis.

Antimuscarinic agents may suppress intestinal motility and produce paralytic ileus with resultant precipitation of toxic megacolon. These drugs should be administered cautiously to patients with ulcerative colitis.

Urinary Retention

Major:

Extendryl Chews

The methscopolamine in Extendryl Chews has a major potential interaction with Urinary Retention.

In general, the use of anticholinergic agents is contraindicated in patients with urinary retention and bladder neck obstruction caused by prostatic hypertrophy. Dysuria may occur and may require catheterization. Also, anticholinergic drugs may aggravate partial obstructive uropathy. Caution is advised even when using agents with mild to moderate anticholinergic activity, particularly in elderly patients.

Moderate:

Extendryl Chews

The chlorpheniramine in Extendryl Chews has a moderate potential interaction with Urinary Retention.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

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dulaglutide

A total of 325 drugs are known to interact with dulaglutide.

Extendryl Chews

A total of 568 drugs are known to interact with Extendryl Chews.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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