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Interactions between Equibron G and Tacrolimus

1 drug interaction and 36 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

theophylline tacrolimus

Applies to: Equibron G (guaifenesin / theophylline) and tacrolimus
Monitor

Coadministration of sirolimus or tacrolimus with other drugs that are also metabolized by CYP450 3A4 may result in elevated plasma concentrations of the macrolide immunosuppressant and/or the coadministered drug(s). The mechanism is decreased drug clearance due to competitive inhibition of CYP450 3A4 activity. Although clinical data are lacking, the possibility of prolonged and/or increased pharmacologic effects of the drugs should be considered.

Management

Pharmacologic responses and/or plasma drug levels should be monitored more closely whenever a macrolide immunosuppressant or another substrate of CYP450 3A4 is added to or withdrawn from therapy, and the dosage(s) adjusted as necessary.

References (2)
  1. (2001) "Product Information. Prograf (tacrolimus)." Fujisawa
  2. (2001) "Product Information. Rapamune (sirolimus)." Wyeth-Ayerst Laboratories

Food/lifestyle interactions

Major food/lifestyle interactions

Major:

tacrolimus Food/Lifestyle

Applies to: tacrolimus
Generally avoid

Grapefruit and/or grapefruit juice may increase the plasma concentrations of tacrolimus. The proposed mechanism for the interaction is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. Inhibition of hepatic CYP450 3A4 may also contribute. Although clinical data are lacking, this interaction may result in increased risk of serious adverse reactions such as nephro- and neurotoxicity, as well as other adverse effects associated with tacrolimus such as malignancies, infections, diabetes, hyperkalemia, hypertension, and QT prolongation.

Generally avoid

Alcohol may modify the rate of tacrolimus release from extended release formulations, thereby potentially increasing the risk of serious adverse reactions.

Adjust dosing interval

Coadministration with food decreases the rate and extent of tacrolimus absorption. This effect is greatest after a high-fat meal.

Management

Patients should avoid consumption of food or drink containing grapefruit during treatment with tacrolimus. Concomitant use of tacrolimus, especially extended release formulations, with alcohol should also be avoided. Tacrolimus extended release formulations should be administered on an empty stomach, at least 1 hour before or 2 hours after a meal, and tacrolimus immediate release formulations should be taken consistently every day with or without food.

References (18)
  1. (2001) "Product Information. Prograf (tacrolimus)." Fujisawa
  2. Hooks MA (1994) "Tacrolimus, a new immunosuppressant--a review of the literature." Ann Pharmacother, 28, p. 501-11
  3. (2022) "Product Information. Adoport (tacrolimus)." Sandoz Ltd
  4. (2024) "Product Information. TACrolimus (Sandoz) (TACrolimus)." Sandoz Pty Ltd
  5. (2023) "Product Information. Prograf (tacrolimus)." Astellas Pharma US, Inc
  6. (2023) "Product Information. Astagraf XL (tacrolimus)." Astellas Pharma US, Inc
  7. (2025) "Product Information. Envarsus XR (tacrolimus)." Veloxis Pharmaceuticals
  8. (2024) "Product Information. Prograf (tacrolimus)." Astellas Pharma Canada Inc
  9. (2024) "Product Information. Advagraf (tacrolimus)." Astellas Pharma Canada Inc
  10. (2024) "Product Information. Envarsus PA (tacrolimus)." Endo Operations LTD
  11. (2024) "Product Information. Dailiport (tacrolimus)." Sandoz Ltd
  12. (2025) "Product Information. Prograf (tacrolimus)." Astellas Pharma Ltd
  13. (2025) "Product Information. Envarsus (tacrolimus)." Chiesi Ltd
  14. (2025) "Product Information. Advagraf (tacrolimus)." Astellas Pharma Ltd
  15. (2025) "Product Information. Modigraf (tacrolimus)." Astellas Pharma Ltd
  16. (2024) "Product Information. Advagraf XL (TACrolimus)." Astellas Pharma Australia Pty Ltd
  17. (2024) "Product Information. proGRAF (TACrolimus)." Astellas Pharma Australia Pty Ltd
  18. (2024) "Product Information. TACrolimus XR (Sandoz) (TACrolimus)." Sandoz Pty Ltd

Moderate food/lifestyle interactions

Moderate:

theophylline Food/Lifestyle

Applies to: Equibron G (guaifenesin / theophylline)
Generally avoid

Coadministration with caffeine may increase the serum concentrations of theophylline. The proposed mechanism involves competitive inhibition of theophylline metabolism via CYP450 1A2, as well as metabolic conversion of caffeine to theophylline in vivo and saturation of theophylline metabolism at higher serum concentrations. In six healthy male volunteers (all smokers), serum concentrations of theophylline (administered as aminophylline 400 mg single oral dose) were significantly higher following consumption of caffeine (2 to 7 cups of instant coffee over 24 hours, equivalent to approximately 120 to 630 mg of caffeine) than after caffeine deprivation for 48 hours. Caffeine consumption also increased the apparent elimination half-life of theophylline by an average of 32% and reduced its total body clearance by 23%. In another study, steady-state concentration and area under the concentration-time curve of theophylline (1200 mg intravenously over 24 hours) increased by 23% and 40%, respectively, in eight healthy volunteers following administration of caffeine (300 mg orally three times a day).

Management

Given the narrow therapeutic index of theophylline, patients should limit or avoid significant fluctuations in their intake of pharmacologic as well as dietary caffeine.

Adjust dosing interval

Administration of theophylline with continuous enteral nutrition may reduce the serum levels or the rate of absorption of theophylline. The mechanism has not been reported. In one case, theophylline levels decreased by 53% in a patient receiving continuous nasogastric tube feedings and occurred with both theophylline tablet and liquid formulations, but not with intravenous aminophylline.

Management

When administered to patients receiving continuous enteral nutrition , some experts recommend that the tube feeding should be interrupted for at least 1 hour before and 1 hour after the dose of theophylline is given; rapid-release formulations are preferable, and theophylline levels should be monitored.

References (3)
  1. Jonkman JH, Sollie FA, Sauter R, Steinijans VW (1991) "The influence of caffeine on the steady-state pharmacokinetics of theophylline." Clin Pharmacol Ther, 49, p. 248-55
  2. Sato J, Nakata H, Owada E, Kikuta T, Umetsu M, Ito K (1993) "Influence of usual intake of dietary caffeine on single-dose kinetics of theophylline in healthy human subjects." Eur J Clin Pharmacol, 44, p. 295-8
  3. Wohlt PD, Zheng L, Gunderson S, Balzar SA, Johnson BD, Fish JT (2009) "Recommendations for the use of medications with continuous enteral nutrition." Am J Health Syst Pharm, 66, p. 1438-67
Moderate:

theophylline Caffeine

Applies to: Equibron G (guaifenesin / theophylline)
Generally avoid

Coadministration with caffeine may increase the serum concentrations of theophylline. The proposed mechanism involves competitive inhibition of theophylline metabolism via CYP450 1A2, as well as metabolic conversion of caffeine to theophylline in vivo and saturation of theophylline metabolism at higher serum concentrations. In six healthy male volunteers (all smokers), serum concentrations of theophylline (administered as aminophylline 400 mg single oral dose) were significantly higher following consumption of caffeine (2 to 7 cups of instant coffee over 24 hours, equivalent to approximately 120 to 630 mg of caffeine) than after caffeine deprivation for 48 hours. Caffeine consumption also increased the apparent elimination half-life of theophylline by an average of 32% and reduced its total body clearance by 23%. In another study, steady-state concentration and area under the concentration-time curve of theophylline (1200 mg intravenously over 24 hours) increased by 23% and 40%, respectively, in eight healthy volunteers following administration of caffeine (300 mg orally three times a day).

Management

Given the narrow therapeutic index of theophylline, patients should limit or avoid significant fluctuations in their intake of pharmacologic as well as dietary caffeine.

References (2)
  1. Jonkman JH, Sollie FA, Sauter R, Steinijans VW (1991) "The influence of caffeine on the steady-state pharmacokinetics of theophylline." Clin Pharmacol Ther, 49, p. 248-55
  2. Sato J, Nakata H, Owada E, Kikuta T, Umetsu M, Ito K (1993) "Influence of usual intake of dietary caffeine on single-dose kinetics of theophylline in healthy human subjects." Eur J Clin Pharmacol, 44, p. 295-8
Moderate:

theophylline Nicotine

Applies to: Equibron G (guaifenesin / theophylline)
Monitor

Smoking cessation may lead to elevated plasma concentrations and enhanced pharmacologic effects of drugs that are substrates of CYP450 1A2 (and possibly CYP450 1A1) and/or certain drugs with a narrow therapeutic index (e.g., flecainide, pentazocine). One proposed mechanism is related to the loss of CYP450 1A2 and 1A1 induction by polycyclic aromatic hydrocarbons in tobacco smoke; when smoking cessation agents are initiated and smoking stops, the metabolism of certain drugs may decrease leading to increased plasma concentrations. The mechanism by which smoking cessation affects narrow therapeutic index drugs that are not known substrates of CYP450 1A2 or 1A1 is unknown. The clinical significance of this interaction is unknown as clinical data are lacking.

Management

Until more information is available, caution is advisable if smoking cessation agents are used concomitantly with drugs that are substrates of CYP450 1A2 or 1A1 and/or those with a narrow therapeutic range. Patients receiving smoking cessation agents may require periodic dose adjustments and closer clinical and laboratory monitoring of medications that are substrates of CYP450 1A2 or 1A1.

References (4)
  1. (2024) "Product Information. Cytisine (cytisinicline)." Consilient Health Ltd
  2. jeong sh, Newcombe D, sheridan j, Tingle M (2015) "Pharmacokinetics of cytisine, an a4 b2 nicotinic receptor partial agonist, in healthy smokers following a single dose." Drug Test Anal, 7, p. 475-82
  3. Vaughan DP, Beckett AH, Robbie DS (1976) "The influence of smoking on the intersubject variation in pentazocine elimination." Br J Clin Pharmacol, 3, p. 279-83
  4. Zevin S, Benowitz NL (1999) "Drug interactions with tobacco smoking: an update" Clin Pharmacokinet, 36, p. 425-38

Disease interactions

32 potential interactions Applies to: 28 conditions, including High Blood Pressure, GERD, Underactive Thyroid, Heart Failure, and Heart Attack.

Angina

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Angina.

The use of theophyllines is associated with an increase in heart rate which may progress to supraventricular tachycardia or ventricular arrhythmia at high serum drug concentrations. Appearance of cardiac adverse effects is generally an indication of theophylline toxicity, although patients with a history of tachyarrhythmias may be more susceptible to the chronotropic effect of these drugs. Therapy with theophyllines should be administered cautiously in such patients. Caution is also advised in patients with hypertension, hyperthyroidism, angina pectoris, or recent myocardial infarction, since high dosages of the drugs are associated with positive inotropic as well as chronotropic effects. Clinical monitoring of serum drug concentrations is recommended to prevent toxicity.

Cardiovascular Conditions and Disorders

Major:

tacrolimus

Tacrolimus has a major potential interaction with Cardiovascular Conditions and Disorders.

Tacrolimus may prolong the QT/QTc interval and may cause Torsade de Pointes. It is recommended to avoid tacrolimus in patients with congenital long QT syndrome. In patients with congestive heart failure, bradyarrhythmias, those taking certain antiarrhythmic medications or other medicinal products that lead to QT prolongation, and those with electrolyte disturbances such as hypokalemia, hypocalcemia, or hypomagnesemia, consider monitoring of tacrolimus whole blood concentrations and obtaining electrocardiograms and monitoring electrolytes (magnesium, potassium, calcium) periodically during treatment.

Cerebral Vascular Disorder

Major:

Equibron G

The theophylline in Equibron G has a major potential interaction with Cerebral Vascular Disorder.

The use of theophyllines is considered by some manufacturers to be contraindicated in patients with underlying seizure disorders unless they are receiving adequate anticonvulsant therapy. Theophyllines may cause seizures, which have generally been associated with toxic drug levels but have also been reported at therapeutic concentrations in patients with head trauma or cerebral infarct. If theophylline therapy is administered in patients with these or other risk factors for seizures, serum drug levels should be monitored closely and maintained in the low therapeutic range. Intractable seizures and death have been reported during acute theophylline toxicity.

Cor Pulmonale

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Cor Pulmonale.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

Diabetes Mellitus

Major:

tacrolimus

Tacrolimus has a major potential interaction with Diabetes Mellitus.

Tacrolimus can induce post-transplant insulin-dependent diabetes mellitus (PTDM). Temporary insulin therapy has been required in some patients, while long-term insulin use has been necessary in others. Reversible insulin dependence has occurred in kidney and liver transplant patients. PTDM has occurred in a greater percentage of tacrolimus-treated (20%) versus cyclosporine-treated (4%) kidney transplant patients. Black and Hispanic patients are at increased risk for PTDM. Therapy with tacrolimus should be administered cautiously in patients with pre-transplant diabetes mellitus.

Electrolyte Abnormalities

Major:

tacrolimus

Tacrolimus has a major potential interaction with Electrolyte Abnormalities.

Tacrolimus may prolong the QT/QTc interval and may cause Torsade de Pointes. It is recommended to avoid tacrolimus in patients with congenital long QT syndrome. In patients with congestive heart failure, bradyarrhythmias, those taking certain antiarrhythmic medications or other medicinal products that lead to QT prolongation, and those with electrolyte disturbances such as hypokalemia, hypocalcemia, or hypomagnesemia, consider monitoring of tacrolimus whole blood concentrations and obtaining electrocardiograms and monitoring electrolytes (magnesium, potassium, calcium) periodically during treatment.

Fever

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Fever.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

GERD

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with GERD.

Methylxanthines increase gastric acidity and may also relax lower esophageal sphincter, which can lead to gastric reflux into the esophagus. Therapy with products containing methylxanthines should be administered cautiously in patients with significant gastroesophageal reflux.

Head Injury

Major:

Equibron G

The theophylline in Equibron G has a major potential interaction with Head Injury.

The use of theophyllines is considered by some manufacturers to be contraindicated in patients with underlying seizure disorders unless they are receiving adequate anticonvulsant therapy. Theophyllines may cause seizures, which have generally been associated with toxic drug levels but have also been reported at therapeutic concentrations in patients with head trauma or cerebral infarct. If theophylline therapy is administered in patients with these or other risk factors for seizures, serum drug levels should be monitored closely and maintained in the low therapeutic range. Intractable seizures and death have been reported during acute theophylline toxicity.

Heart Attack

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Heart Attack.

The use of theophyllines is associated with an increase in heart rate which may progress to supraventricular tachycardia or ventricular arrhythmia at high serum drug concentrations. Appearance of cardiac adverse effects is generally an indication of theophylline toxicity, although patients with a history of tachyarrhythmias may be more susceptible to the chronotropic effect of these drugs. Therapy with theophyllines should be administered cautiously in such patients. Caution is also advised in patients with hypertension, hyperthyroidism, angina pectoris, or recent myocardial infarction, since high dosages of the drugs are associated with positive inotropic as well as chronotropic effects. Clinical monitoring of serum drug concentrations is recommended to prevent toxicity.

Heart Failure

Major:

tacrolimus

Tacrolimus has a major potential interaction with Heart Failure.

Tacrolimus may prolong the QT/QTc interval and may cause Torsade de Pointes. It is recommended to avoid tacrolimus in patients with congenital long QT syndrome. In patients with congestive heart failure, bradyarrhythmias, those taking certain antiarrhythmic medications or other medicinal products that lead to QT prolongation, and those with electrolyte disturbances such as hypokalemia, hypocalcemia, or hypomagnesemia, consider monitoring of tacrolimus whole blood concentrations and obtaining electrocardiograms and monitoring electrolytes (magnesium, potassium, calcium) periodically during treatment.

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Heart Failure.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

Hemodialysis

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Hemodialysis.

Theophylline is removed by hemodialysis. Doses should either be scheduled for administration after dialysis or supplemental doses be given after dialysis.

High Blood Pressure

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with High Blood Pressure.

The use of theophyllines is associated with an increase in heart rate which may progress to supraventricular tachycardia or ventricular arrhythmia at high serum drug concentrations. Appearance of cardiac adverse effects is generally an indication of theophylline toxicity, although patients with a history of tachyarrhythmias may be more susceptible to the chronotropic effect of these drugs. Therapy with theophyllines should be administered cautiously in such patients. Caution is also advised in patients with hypertension, hyperthyroidism, angina pectoris, or recent myocardial infarction, since high dosages of the drugs are associated with positive inotropic as well as chronotropic effects. Clinical monitoring of serum drug concentrations is recommended to prevent toxicity.

Moderate:

tacrolimus

Tacrolimus has a moderate potential interaction with High Blood Pressure.

The use of tacrolimus has been associated with hypertension. Therapy with tacrolimus should be administered cautiously in patients with elevated blood pressure. Close monitoring of blood pressure is recommended.

Hyperkalemia

Moderate:

tacrolimus

Tacrolimus has a moderate potential interaction with Hyperkalemia.

The use of tacrolimus has been associated with hyperkalemia. Therapy with tacrolimus should be administered cautiously in patients with elevated serum potassium levels. Close monitoring of potassium levels is recommended. Careful consideration should be given prior to use of other agents also associated with hyperkalemia (e.g., potassium-sparing diuretics, ACE inhibitors, angiotensin receptor blockers) during tacrolimus therapy.

Hyperthyroidism

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Hyperthyroidism.

The use of theophyllines is associated with an increase in heart rate which may progress to supraventricular tachycardia or ventricular arrhythmia at high serum drug concentrations. Appearance of cardiac adverse effects is generally an indication of theophylline toxicity, although patients with a history of tachyarrhythmias may be more susceptible to the chronotropic effect of these drugs. Therapy with theophyllines should be administered cautiously in such patients. Caution is also advised in patients with hypertension, hyperthyroidism, angina pectoris, or recent myocardial infarction, since high dosages of the drugs are associated with positive inotropic as well as chronotropic effects. Clinical monitoring of serum drug concentrations is recommended to prevent toxicity.

Immunodeficiency

Major:

tacrolimus

Tacrolimus has a major potential interaction with Immunodeficiency.

Due to immunosuppression, patients receiving tacrolimus are at increased risk for infections, including polyoma virus infections, post-transplant lymphoproliferative disorder (PTLD) and CMV viremia and CMV disease. Polyoma virus infections in transplant patients may have serious, and sometimes fatal, outcomes. These include polyoma virus-associated nephropathy (PVAN), mostly due to BK virus infection, and JC virus-associated progressive multifocal leukoencephalopathy (PML). Cases of PML have been reported in patients treated with tacrolimus. Risk factors for PML include treatment with immunosuppressant therapies and impairment of immune function. PTLD associated with Epstein-Barr Virus (EBV), has been reported in immunosuppressed organ transplant patients. Patients that are Epstein-Barr Virus (EBV) seronegative appears to have the greatest risk of developing PTLD. It is recommended to monitor EBV serology during tacrolimus therapy. Caution and patient monitoring is recommended when using this drug in immunosuppressed patients.

Infection

Major:

tacrolimus

Tacrolimus has a major potential interaction with Infection.

Due to immunosuppression, patients receiving tacrolimus are at increased risk for infections, including polyoma virus infections, post-transplant lymphoproliferative disorder (PTLD) and CMV viremia and CMV disease. Polyoma virus infections in transplant patients may have serious, and sometimes fatal, outcomes. These include polyoma virus-associated nephropathy (PVAN), mostly due to BK virus infection, and JC virus-associated progressive multifocal leukoencephalopathy (PML). Cases of PML have been reported in patients treated with tacrolimus. Risk factors for PML include treatment with immunosuppressant therapies and impairment of immune function. PTLD associated with Epstein-Barr Virus (EBV), has been reported in immunosuppressed organ transplant patients. Patients that are Epstein-Barr Virus (EBV) seronegative appears to have the greatest risk of developing PTLD. It is recommended to monitor EBV serology during tacrolimus therapy. Caution and patient monitoring is recommended when using this drug in immunosuppressed patients.

Influenza

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Influenza.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

Liver Disease

Major:

tacrolimus

Tacrolimus has a major potential interaction with Liver Disease.

Tacrolimus undergoes significant hepatic metabolism, primarily by CYP450 3A enzymes. Less than 5% of tacrolimus is eliminated unchanged in the bile and <1% is eliminated unchanged in the urine. Moderate or severe hepatic dysfunction or impaired post-transplant hepatic function may alter the metabolic and therapeutic activity of tacrolimus and increase the whole blood tacrolimus concentration. Therapy with tacrolimus should be administered cautiously and dosage adjustments considered in the presence of moderate or severe hepatic impairment.

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Liver Disease.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

Panhypopituitarism

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Panhypopituitarism.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

Peptic Ulcer

Major:

Equibron G

The theophylline in Equibron G has a major potential interaction with Peptic Ulcer.

Methylxanthines are known to stimulate peptic acid secretion. Therapy with products containing methylxanthines should be administered with extreme caution in patients with active peptic ulcer disease. Some manufacturers consider their use to be contraindicated under such circumstance.

Post MI Syndrome

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Post MI Syndrome.

The use of theophyllines is associated with an increase in heart rate which may progress to supraventricular tachycardia or ventricular arrhythmia at high serum drug concentrations. Appearance of cardiac adverse effects is generally an indication of theophylline toxicity, although patients with a history of tachyarrhythmias may be more susceptible to the chronotropic effect of these drugs. Therapy with theophyllines should be administered cautiously in such patients. Caution is also advised in patients with hypertension, hyperthyroidism, angina pectoris, or recent myocardial infarction, since high dosages of the drugs are associated with positive inotropic as well as chronotropic effects. Clinical monitoring of serum drug concentrations is recommended to prevent toxicity.

Pulmonary Edema

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Pulmonary Edema.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

Renal Dysfunction

Major:

Equibron G

The theophylline in Equibron G has a major potential interaction with Renal Dysfunction.

The metabolites of theophylline, which are generally undetectable in patients with normal renal function, may accumulate in patients with renal impairment and contribute to the toxicity of theophylline. In addition, the plasma protein binding of theophylline may be significantly decreased in renal impairment, resulting in elevated free drug concentrations and further increasing the risk of toxicity. Therapy with theophyllines should be administered cautiously in patients with impaired renal function. Dosage adjustments and more intensive monitoring of serum theophylline concentrations may be required.

Major:

tacrolimus

Tacrolimus has a major potential interaction with Renal Dysfunction.

Nephrotoxicity has been reported in 52% of kidney and 40% of liver transplant patients. Renal toxicity includes increasing serum creatinine and blood urea nitrogen, and renal failure sometimes requiring hemodialysis. Oliguria and hematuria also have been reported. The mechanism of tacrolimus-induced renal dysfunction is not well established. Renal toxicity appears to be dose-related, although toxicity may still occur even at suggested therapeutic concentrations. Therapy with tacrolimus should be administered cautiously and dosage reductions may be necessary in patients with compromised renal function. Alternative immunosuppressive therapy should be considered in the presence of persistent or worsening renal dysfunction.

Seizures

Major:

Equibron G

The theophylline in Equibron G has a major potential interaction with Seizures.

The use of theophyllines is considered by some manufacturers to be contraindicated in patients with underlying seizure disorders unless they are receiving adequate anticonvulsant therapy. Theophyllines may cause seizures, which have generally been associated with toxic drug levels but have also been reported at therapeutic concentrations in patients with head trauma or cerebral infarct. If theophylline therapy is administered in patients with these or other risk factors for seizures, serum drug levels should be monitored closely and maintained in the low therapeutic range. Intractable seizures and death have been reported during acute theophylline toxicity.

Shock

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Shock.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

Tachyarrhythmia

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Tachyarrhythmia.

The use of theophyllines is associated with an increase in heart rate which may progress to supraventricular tachycardia or ventricular arrhythmia at high serum drug concentrations. Appearance of cardiac adverse effects is generally an indication of theophylline toxicity, although patients with a history of tachyarrhythmias may be more susceptible to the chronotropic effect of these drugs. Therapy with theophyllines should be administered cautiously in such patients. Caution is also advised in patients with hypertension, hyperthyroidism, angina pectoris, or recent myocardial infarction, since high dosages of the drugs are associated with positive inotropic as well as chronotropic effects. Clinical monitoring of serum drug concentrations is recommended to prevent toxicity.

Underactive Thyroid

Moderate:

Equibron G

The theophylline in Equibron G has a moderate potential interaction with Underactive Thyroid.

Certain conditions have been identified as causes of reduced theophylline clearance. They include age (neonates and infants < 1 year as well as elderly patients > 60 years) and the following concurrent diseases: acute pulmonary edema; decompensated heart failure; cor pulmonale; fever (>= 102 degrees for 24 hours or more, or lesser temperature elevations for longer periods); influenza; untreated or uncontrolled hypothyroidism; liver disease, cirrhosis or acute hepatitis; reduced renal function in infants < 3 months of age; sepsis with multi-organ failure; and shock. Therapy with theophyllines should be administered cautiously in patients presenting with one or more of these risk factors, and the dosage should be appropriately reduced to prevent toxicity. More intensive monitoring of serum theophylline concentrations may be required. Toxicity is most likely to occur when levels exceed 20 mcg/mL. Severe cases, sometimes without previous warning, have led to cardiac arrhythmias, intractable seizures, and death.

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Equibron G

A total of 335 drugs are known to interact with Equibron G.

tacrolimus

A total of 917 drugs are known to interact with tacrolimus.

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.