Belladonna/ergotamine/phenobarbital and Alcohol/Food Interactions

Ask your doctor before using PHENobarbital together with ethanol (alcohol), this can add to dizziness, drowsiness and other side effects of PHENobarbital. Be careful if you drive or do activities that require you to be awake and alert. Talk with your doctor before using any medications together, or drinking alcohol with PHENobarbital. 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.

PHENobarbital may reduce the blood levels and effects of ergotamine. Contact your doctor if your symptoms worsen or your condition changes during treatment with these medications. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring 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.

Ask your doctor before using belladonna together with ethanol (alcohol). Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking belladonna. You should be warned not to exceed recommended dosages and to avoid activities requiring mental alertness. If your doctor prescribes these medications together, you may need a dose adjustment to safely take this combination. 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.

Nicotine may increase the effects of ergotamine in narrowing the blood vessels and decreasing blood flow. A severe decrease in blood flow to the brain and other parts of the body can lead to dangerous side effects. Contact your doctor immediately if you experience coldness, paleness, discoloration, numbness, tingling, or pain in your hands or feet; muscle pain or weakness; severe or worsening headache; blurred vision; severe abdominal pain; chest pain; or shortness of breath while using these 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.

PHENobarbital may reduce the blood levels and effects of ergotamine. Contact your doctor if your symptoms worsen or your condition changes during treatment with these medications. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring 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.

Consumer information for this interaction is not currently available.

MONITOR: Grapefruit juice may increase the plasma concentrations of orally administered drugs that are substrates of the CYP450 3A4 isoenzyme. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. Because grapefruit juice inhibits primarily intestinal rather than hepatic CYP450 3A4, the magnitude of interaction is greatest for those drugs that undergo significant presystemic metabolism by CYP450 3A4 (i.e., drugs with low oral bioavailability). In general, the effect of grapefruit juice is concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. Pharmacokinetic interactions involving grapefruit juice are also subject to a high degree of interpatient variability, thus the extent to which a given patient may be affected is difficult to predict.

MANAGEMENT: Patients who regularly consume grapefruit or grapefruit juice should be monitored for adverse effects and altered plasma concentrations of drugs that undergo significant presystemic metabolism by CYP450 3A4. Grapefruit and grapefruit juice should be avoided if an interaction is suspected. Orange juice is not expected to interact with these drugs.

barbiturates IV - cardiovascular

The intravenous administration of barbiturates may produce severe cardiovascular reactions such as bradycardia, hypertension, or vasodilation with fall in blood pressure, particularly during rapid infusion. Parenteral therapy with barbiturates should be administered cautiously in patients with hypertension, hypotension, or cardiac disease. The intravenous administration of barbiturates should be reserved for emergency treatment of acute seizures or for anesthesia.

ergot alkaloids - vasospastic reactions

The use of ergot alkaloids is contraindicated in patients with conditions predisposing them to vasospastic reactions, including, ischemic heart disease (angina, history of myocardial infarction, silent ischemia), peripheral vascular disease, sepsis, shock, vascular surgery, uncontrolled hypertension, and severely impaired hepatic or renal function. The vasoconstriction produced be ergot alkaloids may exacerbate these conditions. Ergot alkaloids may cause vasospastic reactions other than coronary artery vasospasm such as peripheral vascular reactions, and colonic ischemia, causing muscle pains, numbness, coldness, pallor, and cyanosis of the digits. In patients with compromised circulation, persistent vasospasm may result in gangrene or death. Nitroprusside and heparin have been used to treat ergotamine- induced severe vasoconstriction.

anticholinergics - hypertension

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