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Can you take Isosorbide mononitrate with Phentolamine?

1 drug interaction and 24 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

isosorbide mononitrate phentolamine

Applies to: isosorbide mononitrate and phentolamine

The following interaction applies only if you are receiving phentolamine by injection into a vein or muscle. Using phentolamine together with isosorbide mononitrate can further decrease your blood pressure. Talk to your doctor if you have any questions or concerns. 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:

phentolamine Food/Lifestyle

Applies to: phentolamine

The following interaction applies only when phentolamine is used as part of a combination containing both papaverine and phentolamine that is injected into the penis. Smoking tobacco before using phentolamine to achieve an erection may reduce the effect of the treatment. Avoid smoking for at least 1 hour before the injection with phentolamine. If the treatment does not work as expected, do not repeat the injection or increase your dose without first talking to your doctor. Talk to a healthcare professional if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs.

Moderate:

isosorbide mononitrate Alcohol (Ethanol)

Applies to: isosorbide mononitrate

Ethanol and isosorbide mononitrate may have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, or changes in pulse or heart rate, especially when treatment is started, the dose is changed, or treatment is restarted. Tell your doctor promptly if these symptoms occur and seek urgent medical help if you faint or have severe dizziness. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. 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:

phentolamine Alcohol (Ethanol)

Applies to: phentolamine

Ethanol and phentolamine may have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, or changes in pulse or heart rate, especially when treatment is started, the dose is changed, or treatment is restarted. Tell your doctor promptly if these symptoms occur and seek urgent medical help if you faint or have severe dizziness. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. 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

21 potential interactions Applies to: 21 conditions, including Heart Failure, Heart Attack, Arrhythmia, Hypotension, and Anemia.

Anemia

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Anemia.

Some manufacturers and medical references consider the use of nitrates and nitrites to be contraindicated in patients with severe anemia. Nitrates and nitrites can cause methemoglobinemia, primarily in high-dose intravenous therapy or acute poisoning and in patients with NADH reductase deficiency. However, elevations of methemoglobin may also occur with commonly used dosages. While probably not of routine clinical significance, the increases may be important in certain patient populations such as those with coronary insufficiency or anemia.

Aortic Stenosis

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Aortic Stenosis.

Organic nitrates and nitrites may cause severe hypotension, syncope and shock, even with small doses. Hypotension induced by these agents may be accompanied by paradoxical bradycardia and increased angina pectoris. Therapy with nitrates and nitrites should be administered cautiously in patients who are volume-depleted or hypotensive (e.g., systolic blood pressure <90 mm Hg) or who, because of inadequate circulation to the brain or to other vital organs, would be unusually compromised by undue hypotension. Patients should be in a sitting or recumbent position during and immediately after drug administration, and monitored for symptoms of severe hypotension such as nausea, vomiting, weakness, pallor, perspiration, and syncope. Nitrate or nitrite therapy is considered contraindicated in patients with acute circulatory failure or shock.

Arrhythmia

Major:

phentolamine

Phentolamine has a major potential interaction with Arrhythmia.

The use of phentolamine is contraindicated in patients with myocardial infarction, or a history of myocardial infarction, coronary artery disease or insufficiency, or angina. Hypotension due to decreased peripheral vascular resistance results from direct relaxation of vascular smooth muscle and/or alpha adrenergic blockade. Heart rate and cardiac output are increased due to beta adrenergic agonist properties. Acute and prolonged hypotensive episodes with reflex tachycardia and arrhythmia have also occurred during phentolamine therapy.

Brain Tumor

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Brain Tumor.

Organic nitrates and nitrites can increase cerebrospinal fluid pressure. Therapy with these agents should be administered cautiously, if at all, in patients with or at risk for intracranial hypertension, including those with cerebral hemorrhage, intracranial lesions, or recent head trauma.

Cerebral Vascular Disorder

Moderate:

phentolamine

Phentolamine has a moderate potential interaction with Cerebral Vascular Disorder.

Cerebrovascular spasms and occlusions have occurred as a result of marked hypotension during phentolamine therapy. Therapy with phentolamine should be administered cautiously in patients with or a history of cerebrovascular disorders.

Cerebrovascular Insufficiency

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Cerebrovascular Insufficiency.

Organic nitrates and nitrites may cause severe hypotension, syncope and shock, even with small doses. Hypotension induced by these agents may be accompanied by paradoxical bradycardia and increased angina pectoris. Therapy with nitrates and nitrites should be administered cautiously in patients who are volume-depleted or hypotensive (e.g., systolic blood pressure <90 mm Hg) or who, because of inadequate circulation to the brain or to other vital organs, would be unusually compromised by undue hypotension. Patients should be in a sitting or recumbent position during and immediately after drug administration, and monitored for symptoms of severe hypotension such as nausea, vomiting, weakness, pallor, perspiration, and syncope. Nitrate or nitrite therapy is considered contraindicated in patients with acute circulatory failure or shock.

Constrictive Pericarditis

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Constrictive Pericarditis.

Organic nitrates and nitrites may cause severe hypotension, syncope and shock, even with small doses. Hypotension induced by these agents may be accompanied by paradoxical bradycardia and increased angina pectoris. Therapy with nitrates and nitrites should be administered cautiously in patients who are volume-depleted or hypotensive (e.g., systolic blood pressure <90 mm Hg) or who, because of inadequate circulation to the brain or to other vital organs, would be unusually compromised by undue hypotension. Patients should be in a sitting or recumbent position during and immediately after drug administration, and monitored for symptoms of severe hypotension such as nausea, vomiting, weakness, pallor, perspiration, and syncope. Nitrate or nitrite therapy is considered contraindicated in patients with acute circulatory failure or shock.

Dehydration

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Dehydration.

Organic nitrates and nitrites may cause severe hypotension, syncope and shock, even with small doses. Hypotension induced by these agents may be accompanied by paradoxical bradycardia and increased angina pectoris. Therapy with nitrates and nitrites should be administered cautiously in patients who are volume-depleted or hypotensive (e.g., systolic blood pressure <90 mm Hg) or who, because of inadequate circulation to the brain or to other vital organs, would be unusually compromised by undue hypotension. Patients should be in a sitting or recumbent position during and immediately after drug administration, and monitored for symptoms of severe hypotension such as nausea, vomiting, weakness, pallor, perspiration, and syncope. Nitrate or nitrite therapy is considered contraindicated in patients with acute circulatory failure or shock.

Glaucoma/Intraocular Hypertension

Minor:

isosorbide mononitrate

Isosorbide mononitrate has a minor potential interaction with Glaucoma/Intraocular Hypertension.

Some medical references state that organic nitrates and nitrites may increase intraocular pressure and should be used with caution in patients with glaucoma. However, the effect on intraocular pressure is variable and brief, and there is no evidence that these drugs precipitate narrow-angle glaucoma. Amyl nitrate typically may cause a slight rise of 3+ mm for several seconds followed by a fall in intraocular pressure for 10 to 20 minutes, the latter secondary to a fall in blood pressure. Nitroglycerin rarely produces ocular side effects, and oral nitroglycerin appears to have few to no significant ocular side effects.

Head Injury

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Head Injury.

Organic nitrates and nitrites can increase cerebrospinal fluid pressure. Therapy with these agents should be administered cautiously, if at all, in patients with or at risk for intracranial hypertension, including those with cerebral hemorrhage, intracranial lesions, or recent head trauma.

Heart Attack

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Heart Attack.

The benefits of organic nitrates and nitrites in patients with acute myocardial infarction (AMI) or congestive heart failure have not been established and its use is not recommended in these settings. If used, it should be accompanied by careful clinical and hemodynamic monitoring to avoid the hazards of systemic hypotension and tachycardia, which in AMI can exacerbate myocardial ischemia. In general, oral or long-acting formulations of these drugs should not be used in the early management of AMI because of the difficulty in precisely controlling and rapidly terminating their hemodynamic effects should adverse reactions occur. Sublingual and other immediate- onset nitrates or nitrites should typically be avoided in suspected AMI with marked bradycardia or tachycardia, and should be used with extreme caution, if at all, in patients with right ventricular or inferior wall infarction. Rarely, sublingual nitroglycerin has produced hypotension accompanied by paradoxical bradycardia in patients with AMI and especially right ventricular infarction. The latter group of patients are also particularly dependent on adequate right ventricular preload to maintain cardiac output and can experience profound hypotension with nitrate or nitrite administration due to reduction of right ventricular preload.

Heart Failure

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Heart Failure.

The benefits of organic nitrates and nitrites in patients with acute myocardial infarction (AMI) or congestive heart failure have not been established and its use is not recommended in these settings. If used, it should be accompanied by careful clinical and hemodynamic monitoring to avoid the hazards of systemic hypotension and tachycardia, which in AMI can exacerbate myocardial ischemia. In general, oral or long-acting formulations of these drugs should not be used in the early management of AMI because of the difficulty in precisely controlling and rapidly terminating their hemodynamic effects should adverse reactions occur. Sublingual and other immediate- onset nitrates or nitrites should typically be avoided in suspected AMI with marked bradycardia or tachycardia, and should be used with extreme caution, if at all, in patients with right ventricular or inferior wall infarction. Rarely, sublingual nitroglycerin has produced hypotension accompanied by paradoxical bradycardia in patients with AMI and especially right ventricular infarction. The latter group of patients are also particularly dependent on adequate right ventricular preload to maintain cardiac output and can experience profound hypotension with nitrate or nitrite administration due to reduction of right ventricular preload.

Hemodialysis

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Hemodialysis.

The combined effect of organic nitrates or nitrites with hemodialysis, which often lowers blood pressure, can cause life-threatening hypotension. Therapy with these agents should be administered cautiously in patients requiring hemodialysis. The medication should be withheld before undergoing dialysis, and hemodynamic stability should be established prior to resumption of medication following dialysis. Nitroglycerin and isosorbide dinitrate are moderately dialyzed.

Hemorrhagic Stroke

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Hemorrhagic Stroke.

Organic nitrates and nitrites can increase cerebrospinal fluid pressure. Therapy with these agents should be administered cautiously, if at all, in patients with or at risk for intracranial hypertension, including those with cerebral hemorrhage, intracranial lesions, or recent head trauma.

Hypertrophic Cardiomyopathy

Moderate:

isosorbide mononitrate

Isosorbide mononitrate has a moderate potential interaction with Hypertrophic Cardiomyopathy.

Organic nitrates and nitrites may aggravate the angina associated with hypertrophic cardiomyopathy and should be administered cautiously in patients with this condition.

Hypotension

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Hypotension.

Organic nitrates and nitrites may cause severe hypotension, syncope and shock, even with small doses. Hypotension induced by these agents may be accompanied by paradoxical bradycardia and increased angina pectoris. Therapy with nitrates and nitrites should be administered cautiously in patients who are volume-depleted or hypotensive (e.g., systolic blood pressure <90 mm Hg) or who, because of inadequate circulation to the brain or to other vital organs, would be unusually compromised by undue hypotension. Patients should be in a sitting or recumbent position during and immediately after drug administration, and monitored for symptoms of severe hypotension such as nausea, vomiting, weakness, pallor, perspiration, and syncope. Nitrate or nitrite therapy is considered contraindicated in patients with acute circulatory failure or shock.

Ischemic Heart Disease

Major:

phentolamine

Phentolamine has a major potential interaction with Ischemic Heart Disease.

The use of phentolamine is contraindicated in patients with myocardial infarction, or a history of myocardial infarction, coronary artery disease or insufficiency, or angina. Hypotension due to decreased peripheral vascular resistance results from direct relaxation of vascular smooth muscle and/or alpha adrenergic blockade. Heart rate and cardiac output are increased due to beta adrenergic agonist properties. Acute and prolonged hypotensive episodes with reflex tachycardia and arrhythmia have also occurred during phentolamine therapy.

Liver Disease

Moderate:

phentolamine

Phentolamine has a moderate potential interaction with Liver Disease.

The pharmacokinetic disposition of phentolamine has not been fully determined. Limited data suggest that phentolamine is metabolized by the liver. Phentolamine is eliminated by the kidney and approximately 13% is excreted unchanged in the urine. Therapy with phentolamine should be administered cautiously in patients with severe liver and/or renal function. Clinical monitoring of hepatic and/or renal function is recommended.

Pseudotumor Cerebri

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Pseudotumor Cerebri.

Organic nitrates and nitrites can increase cerebrospinal fluid pressure. Therapy with these agents should be administered cautiously, if at all, in patients with or at risk for intracranial hypertension, including those with cerebral hemorrhage, intracranial lesions, or recent head trauma.

Renal Dysfunction

Moderate:

phentolamine

Phentolamine has a moderate potential interaction with Renal Dysfunction.

The pharmacokinetic disposition of phentolamine has not been fully determined. Limited data suggest that phentolamine is metabolized by the liver. Phentolamine is eliminated by the kidney and approximately 13% is excreted unchanged in the urine. Therapy with phentolamine should be administered cautiously in patients with severe liver and/or renal function. Clinical monitoring of hepatic and/or renal function is recommended.

Shock

Major:

isosorbide mononitrate

Isosorbide mononitrate has a major potential interaction with Shock.

Organic nitrates and nitrites may cause severe hypotension, syncope and shock, even with small doses. Hypotension induced by these agents may be accompanied by paradoxical bradycardia and increased angina pectoris. Therapy with nitrates and nitrites should be administered cautiously in patients who are volume-depleted or hypotensive (e.g., systolic blood pressure <90 mm Hg) or who, because of inadequate circulation to the brain or to other vital organs, would be unusually compromised by undue hypotension. Patients should be in a sitting or recumbent position during and immediately after drug administration, and monitored for symptoms of severe hypotension such as nausea, vomiting, weakness, pallor, perspiration, and syncope. Nitrate or nitrite therapy is considered contraindicated in patients with acute circulatory failure or shock.

More resources

isosorbide mononitrate

A total of 239 drugs are known to interact with isosorbide mononitrate.

phentolamine

A total of 349 drugs are known to interact with phentolamine.

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.