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Mepergan Fortis Side Effects

Generic Name: meperidine / promethazine

Note: This document contains side effect information about meperidine / promethazine. Some of the dosage forms listed on this page may not apply to the brand name Mepergan Fortis.

For the Consumer

Applies to meperidine / promethazine: oral capsule

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Very bad dizziness or passing out.
  • Fast or slow heartbeat.
  • A heartbeat that does not feel normal.
  • Fever or chills.
  • Sore throat.
  • Hallucinations (seeing or hearing things that are not there).
  • Mood changes.
  • Feeling confused.
  • Very hard stools (constipation).
  • Feeling very sleepy.
  • Chest pain.
  • Seizures.
  • Trouble breathing, slow breathing, or shallow breathing.
  • Shakiness.
  • Any unexplained bruising or bleeding.
  • Change in eyesight.
  • Yellow skin or eyes.
  • A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your doctor right away if you have any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or are sweating a lot.
  • Some people who take this drug may have muscle movements that cannot be controlled. Call your doctor right away if you have any trouble controlling body movements or if you have muscle problems with your tongue, face, mouth, or jaw like tongue sticking out, puffing cheeks, mouth puckering, or chewing.
  • A very bad and sometimes deadly health problem called serotonin syndrome may happen if you take this drug with drugs for depression, migraines, or certain other drugs. Call your doctor right away if you have agitation; change in balance; confusion; hallucinations; fever; fast or abnormal heartbeat; flushing; muscle twitching or stiffness; seizures; shivering or shaking; sweating a lot; very bad diarrhea, upset stomach, or throwing up; or very bad headache.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Upset stomach or throwing up.
  • Hard stools (constipation).
  • Dizziness.
  • Feeling sleepy.
  • Dry mouth.
  • Sweating a lot.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

For Healthcare Professionals

Applies to meperidine / promethazine: injectable solution, oral capsule

Nervous system

Central nervous system side effects of meperidine may be either depressant or excitatory. Excitatory symptoms are sometimes ignored as possible side effects of meperidine, but may be due to the accumulation of a metabolite, normeperidine. Accumulation of normeperidine occurs more frequently in patients with renal insufficiency and in patients who are receiving meperidine via a patient-controlled analgesia pump.

Meperidine may increase intracranial pressure, and therefore should be used with caution in patients with head injuries. Severe adverse effects, such as respiratory depression, may be treated with the opioid antagonist naloxone.

A case of seizures has been reported in a patient with porphyria receiving meperidine.[Ref]

Central nervous system adverse effects of meperidine include sleepiness, respiratory depression, delirium, seizures, tremors, dizziness, visual disturbances, muscle twitches, dilated pupils, and Parkinsonian symptoms.

Nervous system side effects are common with the use of promethazine and include excessive sedation, drowsiness, fatigue, paradoxical excitation, and decreased motor coordination. Extrapyramidal effects (including oculogyric crises, torticollis and tongue protrusion), encephalitic symptoms, convulsions, and psychosis have been rarely reported.[Ref]

Psychiatric

Psychiatric adverse effects of meperidine include fearfulness, agitation, paranoia, hypervigilance, and auditory and visual hallucinations.[Ref]

Psychological dependence on meperidine may develop.[Ref]

Gastrointestinal

Meperidine may cause contraction of the sphincter of Oddi, thereby increasing intrabiliary pressure. As a result, meperidine may aggravate rather than relieve biliary colic.

Constipation is less common with meperidine than some other narcotics.[Ref]

Gastrointestinal effects of meperidine including increased gastroesophageal reflux, increased biliary pressure, dry mouth, nausea, and vomiting have been reported.

Gastrointestinal effects of promethazine include nausea and vomiting.[Ref]

Respiratory

There are case reports of bronchospasm occurring in patients with a history of asthma after receiving meperidine. Because of this effect and possible respiratory depression, meperidine should be used with caution in patients with severe reactive or obstructive pulmonary disease.[Ref]

Bronchospasm has been reported with the use of meperidine in patients with underlying pulmonary disease.

Respiratory depression and arrest may occur rarely, especially with parenteral administration of promethazine. Equipment for resuscitation should be available when parenteral promethazine is used.[Ref]

Cardiovascular

Cardiovascular effects including phlebitis have been reported in patients who are receiving meperidine. Hypotension has been reported rarely.

Cardiovascular effects have been rarely observed with the use of promethazine and include tachycardia, bradycardia, and transient hypotension. Prolongation of the QT interval, heart block, and malignant arrhythmias have been reported in association with other phenothiazines.[Ref]

The hypotension reported in patients receiving meperidine occurs most commonly in patients who are under anesthesia, who are dehydrated, and who are receiving other medications.[Ref]

Genitourinary

Genitourinary effects including urinary retention have been reported in patients who are receiving meperidine.[Ref]

Dermatologic

Dermatologic effects including rash and sweating have been reported in patients who are receiving meperidine.[Ref]

Other

The neuroleptic malignant syndrome has been rarely observed during treatment with promethazine.[Ref]

Fever, altered consciousness, autonomic dysfunction, and muscle rigidity are the hallmarks of the neuroleptic malignant syndrome. The neuroleptic malignant syndrome is associated with a case fatality rate of about 20%. Immediate discontinuation of promethazine and intensive monitoring and supportive care are indicated.[Ref]

Local

Inadvertent intra-arterial injection of promethazine carries a high risk of distal necrosis and frequently requires amputation of the affected limb. Subcutaneous injection has more rarely caused chemical irritation and necrosis.[Ref]

Hypersensitivity

Hypersensitivity reactions to promethazine include rare reports of rash, pruritus, hypotension, photosensitivity, and tachycardia.[Ref]

Hematologic

Hematologic effects of promethazine include rare cases of neutropenia.[Ref]

Immunologic

Immunologic reactions with the use of promethazine include rare reports of a systemic lupus erythematosus syndrome.[Ref]

Other

Central and obstructive apneas have been observed in infants given promethazine. Promethazine has been implicated by some as a possible cause of the Sudden Infant Death Syndrome (SIDS).[Ref]

References

1. Drotts DL, Vinson DR "Prochlorperazine induces akathisia in emergency patients." Ann Emerg Med 34 (1999): 469-75

2. Marcantonio ER, Juarez G, Goldman L, et al. "The relationship of postoperative delirium with psychoactive medications." JAMA 272 (1994): 1518-22

3. Hagmeyer KO, Mauro LS, Mauro VF "Meperidine-related seizures associated with patient-controlled analgesia pumps." Ann Pharmacother 27 (1993): 29-32

4. Jones J, Sklar D, Dougherty J, White W "Randomized double-blind trial of intravenous prochlorperazine for the treatment of acute headache." JAMA 261 (1989): 1174-6

5. "Product Information. Compazine (prochlorperazine)." SmithKline Beecham, Philadelphia, PA.

6. Baker FM, Cook P "Compazine complications: a review." J Natl Med Assoc 73 (1981): 409-12

7. Shaw HL "Treatment of intractable cancer pain by electronically controlled parenteral infusion of analgesic drugs." Cancer 72 (1993): 3416-25

8. Geller RJ "Meperidine in patient-controlled analgesia: a near-fatal mishap." Anesth Analg 76 (1993): 655-7

9. Olver IN, Laidlaw CR, Matthews JP, Bishop JF, Hayes AM, Wolf M, Toner GC "A randomised double blind crossover study of domperidone and prochlorperazine suppositories for controlling emesis in outpatients receiving chemotherapy." Eur J Cancer 30a (1994): 426-9

10. Armstrong PJ, Bersten A "Normeperidine toxicity." Anesth Analg 65 (1986): 536-8

11. Samuels SI, Rabinov W "Difficulty reversing drug-induced coma in a patient with sleep apnea." Anesth Analg 65 (1986): 1222-4

12. Olive JM, Masana L, Gonzalez J "Meperidine and reversible parkinsonism." Mov Disord 9 (1994): 115-6

13. Boston Collaborative Drug Surveillance Program "Drug-induced extrapyramidal symptoms." JAMA 224 (1973): 889-91

14. Stone PA, Macintyre PE, Jarvis DA "Norpethidine toxicity and patient controlled analgesia." Br J Anaesth 71 (1993): 738-40

15. Fogarty T, Murray GB "Psychiatric presentation of meperidine toxicity." J Clin Psychopharmacol 7 (1987): 116-7

16. Hey VM, Ostick DG, Mazumder JK, Lord WD "Pethidine, metoclopramide and the gastro-oesophageal sphincter." Anaesthesia 36 (1981): 173-6

17. Stanski DR, Cherry C, Bradley R, et al "Efficacy and safety of single doses of intramuscular ketorolac tromethamine compared with meperidine for postoperative pain." Pharmacotherapy 10 (1990): s40-4

18. Elloway R, Sherman S, Maas L, et al "Meperidine-induced bronchospasm." Gastrointest Endosc 38 (1992): 93

19. Reutens DC, Stewart-Wynne EG "Norpethidine induced myoclonus in a patient with renal failure." J Neurol Neurosurg Psychiatry 52 (1989): 1450-1

20. "Product Information. Demerol (meperidine)." Sanofi Winthrop Pharmaceuticals, New York, NY.

21. Petros JG, Mallen JK, Howe K, Rimm EB, Robillard RJ "Patient-controlled analgesia and postoperative urinary retention after open appendectomy." Surg Gynecol Obstet 177 (1993): 172-5

22. Reilly GD, Wood ML "Prochlorperazine--an unusual cause of lip ulceration." Acta Derm Venereol 64 (1984): 270-1

23. Duxbury AJ, Ead RD, Turner EP "Erosive cheilitis related to prochlorperazine maleate." Br Dent J 153 (1982): 271-2

24. Manser TJ, Warner JF "Neuroleptic malignant syndrome associated with prochlorperazine." South Med J 83 (1990): 73-4

25. Hager DL, Wilson JN "Gangrene of the hand following intra-arterial injection." Arch Surg 94 (1967): 86-9

26. "Product Information. Phenergan (promethazine)." Wyeth-Ayerst Laboratories, Philadelphia, PA.

27. Fabius AJ, Gaulhofer WK "Systemic lupus erythematosus induced by psychotropic drugs." Acta Rheumatol Scand 17 (1971): 137-47

Some side effects of Mepergan Fortis may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.

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