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Can you take Peginterferon alfa-2b with Theophylline?

1 drug interaction and 54 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

theophylline peginterferon alfa-2b

Applies to: theophylline and peginterferon alfa-2b

Treatment with medications like peginterferon alfa-2b may increase the blood levels of theophylline, which can lead to potentially serious and life-threatening side effects. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Contact your doctor if you develop nausea, vomiting, diarrhea, loss of appetite, headache, tremor, confusion, restlessness, insomnia, seizures, heart palpitations, and/or irregular heartbeat, as these may be signs and symptoms of excessive theophylline levels. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Food/lifestyle interactions

Moderate food/lifestyle interactions

Moderate:

theophylline Food/Lifestyle

Applies to: theophylline

Both smoking and excessive caffeine consumption can alter the blood levels of theophylline, which may affect the dosing. Tobacco and marijuana smoke (including secondhand exposure) generally reduces, while caffeine increases, blood levels. In addition, caffeine is a stimulant and may add to the side effects of theophylline such as headache, insomnia, and increases in blood pressure and heart rate. It is best to avoid smoking and to limit caffeine consumption during theophylline therapy. Talk to a healthcare professional if you have any questions or concerns. If you start smoking or undergo smoking cessation, your doctor may need to monitor your blood levels more closely to determine if you need a dose adjustment of theophylline. You should stop taking theophylline and seek medical attention if you experience potential signs and symptoms of excessive drug levels such as nausea, vomiting, persistent headache, insomnia, and rapid heartbeat. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

When theophylline is given with enteral (tube) feedings, blood levels may be decreased due to interference with its absorption. This may reduce the effectiveness of the medication. To minimize potential for interaction, you may interrupt the feeding for one hour before and one hour after the theophylline dose. You may need more frequent blood tests to monitor theophylline levels.

Moderate:

theophylline Caffeine

Applies to: theophylline

Ask your doctor before using theophylline together with caffeine. Using these medications together may increase some of the side effects of theophylline. This can cause nausea, vomiting, insomnia, tremors, restlessness, uneven heartbeats, and seizure (convulsions). Avoid drinks or foods that contain caffeine, such as coffee, tea, cola, and chocolate. You may need a dose adjustment or special test if you use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate:

theophylline Nicotine

Applies to: theophylline

As you stop smoking during treatment with nicotine, your dosage requirement of theophylline may need to be changed. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Disease interactions

51 potential interactions Applies to: 44 conditions, including High Blood Pressure, Depression, GERD, Underactive Thyroid, and Heart Failure.

Angina

Moderate:

theophylline

Theophylline 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.

Arrhythmia

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Arrhythmia.

Hypertension, arrhythmias, angina, myocardial infarction, cardiomyopathy, and congestive heart failure have been reported during interferon therapy. Therapy with interferons should be administered with caution in patients with compromised cardiac function.

Autoimmune Disorders

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Autoimmune Disorders.

Antiviral interferons may exacerbate autoimmune disorders such as myositis, thyroiditis, systemic lupus erythematosus, rheumatoid arthritis, psoriasis, or autoimmune hepatitis. Therapy should be avoided or administered with extreme caution in patients with autoimmune disorders.

Autoimmune Hepatitis

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Autoimmune Hepatitis.

The use of peginterferons alfa are contraindicated in patients with autoimmune hepatitis.

Bone Marrow Depression/Low Blood Counts

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Bone Marrow Depression/Low Blood Counts.

Interferons (alfa and gamma) induce a dose-dependent, generally mild, myelosuppression. Leukopenia is the primary manifestation. Thrombocytopenia and anemia occur less frequently. Therapy with interferons (alfa and gamma) should be administered cautiously to patients with bone marrow suppression. Clinical monitoring of hematopoietic function is recommended.

Cardiovascular Conditions and Disorders

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Cardiovascular Conditions and Disorders.

Hypertension, arrhythmias, angina, myocardial infarction, cardiomyopathy, and congestive heart failure have been reported during interferon therapy. Therapy with interferons should be administered with caution in patients with compromised cardiac function.

Cerebral Vascular Disorder

Major:

theophylline

Theophylline 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.

Cirrhosis

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Cirrhosis.

The use of peginterferons alfa are contraindicated in patients with hepatic decompensation (Child-Pugh score greater than 6, class B or C) in cirrhotic patients before treatment, and in patients with hepatic decompensation (Child-Pugh score greater or equal to 6) that have chronic hepatitis C coinfected with HIV.

Cor Pulmonale

Moderate:

theophylline

Theophylline 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.

Depression

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Depression.

Interferons (alfa or beta) can induce depression and suicidal behavior. Suicidal attempts and suicides have been reported. Therapy with interferons (alfa or beta) should be administered cautiously to patients with or predisposed to mental depression. Clinical monitoring of psychological status is recommended.

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Depression.

Life-threatening or fatal neuropsychiatric reactions have been reported in patients receiving peginterferons alfa, including suicide, suicide ideation, homicidal ideation, depression, relapse of drug addiction, and drug overdose. These reactions have occurred in patients with and without previous psychiatric illness. These drugs should be used with extreme caution in patients with a history of depression. Other events reported include aggressive behavior, psychosis, hallucinations, bipolar disorder and mania. Patients should be monitored for any evidence of depression or other psychiatric symptoms, and they should be advised to report any signs or symptoms of depression or other changes in mood or behavior. In severe cases, therapy should be stopped immediately and psychiatric intervention should be instituted.

Diabetes Mellitus

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Diabetes Mellitus.

Peginterferons alfa can cause or aggravate hypothyroidism, hyperthyroidism, hyperglycemia, hypoglycemia and diabetes mellitus. Treatment should be administered with caution on patients with these conditions. Treatment should not be initiated if the condition cannot be effectively treated by medication. Therapy should be discontinued if any of these conditions develops during treatment and it cannot be controlled with medication.

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Diabetes Mellitus.

Flu-like symptoms frequently associated with interferon-alfa therapy can precipitate ketoacidosis in diabetic patients. Therapy with interferon alfa should be administered cautiously in patients with diabetes mellitus. Clinical monitoring of blood glucose concentrations and anti-diabetic therapy is recommended.

Fever

Moderate:

theophylline

Theophylline 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:

theophylline

Theophylline 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:

theophylline

Theophylline 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:

theophylline

Theophylline 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:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Heart Failure.

Hypertension, arrhythmias, angina, myocardial infarction, cardiomyopathy, and congestive heart failure have been reported during interferon therapy. Therapy with interferons should be administered with caution in patients with compromised cardiac function.

Moderate:

theophylline

Theophylline 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:

theophylline

Theophylline 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.

Hemoglobinopathy

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Hemoglobinopathy.

The use of peginterferon alfa-2b is contraindicated in patients with hemoglobinopathies such as, thalassemia major, and sickle-cell anemia.

High Blood Pressure

Moderate:

theophylline

Theophylline 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.

HIV-1 Infection

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with HIV-1 Infection.

The use of peginterferons alfa are contraindicated in patients with hepatic decompensation (Child-Pugh score greater than 6, class B or C) in cirrhotic patients before treatment, and in patients with hepatic decompensation (Child-Pugh score greater or equal to 6) that have chronic hepatitis C coinfected with HIV.

Hyperthyroidism

Moderate:

theophylline

Theophylline 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.

Hypoglycemia

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Hypoglycemia.

Peginterferons alfa can cause or aggravate hypothyroidism, hyperthyroidism, hyperglycemia, hypoglycemia and diabetes mellitus. Treatment should be administered with caution on patients with these conditions. Treatment should not be initiated if the condition cannot be effectively treated by medication. Therapy should be discontinued if any of these conditions develops during treatment and it cannot be controlled with medication.

Influenza

Moderate:

theophylline

Theophylline 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.

Ischemic Heart Disease

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Ischemic Heart Disease.

Hypertension, arrhythmias, angina, myocardial infarction, cardiomyopathy, and congestive heart failure have been reported during interferon therapy. Therapy with interferons should be administered with caution in patients with compromised cardiac function.

Liver Disease

Moderate:

theophylline

Theophylline 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.

Neutropenia

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Neutropenia.

Peginterferons alfa suppress bone marrow function and may result in severe cytopenias. Very rarely, it may be associated with aplastic anemia. These drugs should be used with caution in patients with baseline neutrophil counts less than 1,500 cells/mm3, with platelet counts less than 90,000 cells/mm3 or baseline hemoglobin less than 10 g/dL. It is advised that complete blood counts be obtained pretreatment and monitored routinely during therapy. Neutropenia and thrombocytopenia occur with greater incidence in patients coinfected with HIV.

Pancreatitis

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Pancreatitis.

Fatal and nonfatal pancreatitis has been observed in patients treated with alpha interferon. Therapy should be suspended in patients with signs and symptoms suggestive of pancreatitis and discontinued in patients diagnosed with pancreatitis.

Panhypopituitarism

Moderate:

theophylline

Theophylline 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.

Parkinsonism

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Parkinsonism.

Reversible CNS effects such as seizures, mental status changes, manic behavior or psychotic reactions, gait disturbances, and dizziness have occurred in patients receiving interferons. Therapy with interferons should be administered cautiously in patients with or predisposed to seizures, psychiatric disorders, or conditions affecting posture or gait.

Peptic Ulcer

Major:

theophylline

Theophylline 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.

Peripheral Neuropathy

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Peripheral Neuropathy.

Paresthesia and numbness have been reported during interferon therapy. Therapy with interferons should be administered cautiously in patients with or predisposed to peripheral neuropathy.

Post MI Syndrome

Moderate:

theophylline

Theophylline 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.

Psychosis

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Psychosis.

Reversible CNS effects such as seizures, mental status changes, manic behavior or psychotic reactions, gait disturbances, and dizziness have occurred in patients receiving interferons. Therapy with interferons should be administered cautiously in patients with or predisposed to seizures, psychiatric disorders, or conditions affecting posture or gait.

Pulmonary Edema

Moderate:

theophylline

Theophylline 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.

Pulmonary Impairment

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Pulmonary Impairment.

Dyspnea, pulmonary infiltrates, pneumonia, bronchiolitis, pulmonary hypertension, and other pulmonary disorders resulting in respiratory failure and/or death may be induced or aggravated by alpha interferon therapy. Caution should be used when used in patients with preexisting pulmonary disorders.

Renal Dysfunction

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Renal Dysfunction.

Proteinuria (rare), not associated with a decrease in serum protein, is the most common renal toxicity observed with interferon- alfa therapy. Increased BUN and serum creatinine levels, hematuria, acute renal failure and nephrotic syndrome have also been reported. Therapy with interferon alfa should be administered cautiously to patients with severe renal dysfunction. Renal function should be evaluated in all patients before initiation of interferon- alfa therapy. In addition, patients with any degree of renal impairment should be carefully monitored for laboratory abnormalities and decreased creatinine clearance. A reduced dose of medication is recommended in patients with low CrCl (less than 50 mL/min - 30 mL/min).

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Renal Dysfunction.

The use of peginterferon alfa-2b is contraindicated in patients with creatinine clearance less than 50 mL/min.

Major:

theophylline

Theophylline 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.

Seizures

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Seizures.

Reversible CNS effects such as seizures, mental status changes, manic behavior or psychotic reactions, gait disturbances, and dizziness have occurred in patients receiving interferons. Therapy with interferons should be administered cautiously in patients with or predisposed to seizures, psychiatric disorders, or conditions affecting posture or gait.

Major:

theophylline

Theophylline 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:

theophylline

Theophylline 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:

theophylline

Theophylline 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.

Thrombocytopenia

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Thrombocytopenia.

Peginterferons alfa suppress bone marrow function and may result in severe cytopenias. Very rarely, it may be associated with aplastic anemia. These drugs should be used with caution in patients with baseline neutrophil counts less than 1,500 cells/mm3, with platelet counts less than 90,000 cells/mm3 or baseline hemoglobin less than 10 g/dL. It is advised that complete blood counts be obtained pretreatment and monitored routinely during therapy. Neutropenia and thrombocytopenia occur with greater incidence in patients coinfected with HIV.

Thyroid Disease

Major:

peginterferon alfa-2b

Peginterferon alfa-2b has a major potential interaction with Thyroid Disease.

Thyroid abnormalities, hypothyroidism or hyperthyroidism, have been reported in patients administered interferons. Therapy with interferons should be administered cautiously to patients with thyroid dysfunction. If thyroid control cannot be maintained within normal limits with medication, interferon-alfa should be discontinued. Clinical monitoring of thyroid function is recommended.

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Thyroid Disease.

Peginterferons alfa can cause or aggravate hypothyroidism, hyperthyroidism, hyperglycemia, hypoglycemia and diabetes mellitus. Treatment should be administered with caution on patients with these conditions. Treatment should not be initiated if the condition cannot be effectively treated by medication. Therapy should be discontinued if any of these conditions develops during treatment and it cannot be controlled with medication.

Ulcerative Colitis

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Ulcerative Colitis.

Fatal and nonfatal ulcerative or hemorrhagic/ischemic colitis have been observed within 12 weeks of the start of alpha interferon treatment. Abdominal pain, bloody diarrhea, and fever are the typical manifestations. Treatment should be discontinued immediately in patients who develop these signs and symptoms. The colitis usually resolves within 1 to 3 weeks of discontinuation of alpha interferons.

Underactive Thyroid

Moderate:

theophylline

Theophylline 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.

Visual Defect/Disturbance

Moderate:

peginterferon alfa-2b

Peginterferon alfa-2b has a moderate potential interaction with Visual Defect/Disturbance.

Decrease or loss of vision, retinopathy including macular edema, retinal artery or vein thrombosis, retinal hemorrhages and cotton wool spots, optic neuritis, papilledema, and serious retinal detachment can be induced or aggravated by alpha interferons. All patients should receive an eye examination at baseline and caution should be exercised in patients with preexisting ophthalmologic disorders. Patients should have periodic ophthalmologic exams during treatment.

More resources

peginterferon alfa-2b

A total of 237 drugs are known to interact with peginterferon alfa-2b.

theophylline

A total of 335 drugs are known to interact with theophylline.

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

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