Prazosin Disease Interactions
There are 2 disease interactions with prazosin:
Alpha-1 Blockers (Includes Prazosin) ↔ Hypotension
Severe Potential Hazard, High plausibility
Applies to: Syncope, Autonomic Neuropathy, Hypotension, Dehydration, Diarrhea, Vomiting
Peripheral alpha 1-adrenergic receptor blocking agents (aka alpha 1-blockers) cause vasodilation and can produce marked hypotension, especially orthostatic hypotension with syncope or other postural symptoms such as dizziness, lightheadedness, and palpitations. Orthostatic effects are most common during initiation of therapy and often occur within 90 minutes after the first dose. However, they can also occur following a dosage increase or resumption of therapy after an interruption of more than a few days. Agents with alpha 1a specificity, such as tamsulosin, act primarily on the prostate but are not devoid of hypotensive effects. Therapy with peripheral alpha-1 blockers should be administered cautiously in patients with or predisposed to hypotensive or syncopal episodes. Caution is also advised in patients who are dehydrated (e.g., due to severe or prolonged diarrhea or vomiting), since they may be more sensitive to the hypotensive effect of the drugs. Therapy should be initiated with the lowest dosage possible and titrated gradually based on patient response and tolerance in accordance with the individual product package labeling. During initiation or reinstitution of therapy and following an increase in dosage, patients should be advised not to rise abruptly from a sitting or recumbent position and to avoid situations where injury could result if syncope occur. Concomitant use of alcohol, extensive periods of standing, prolonged or intense exercise, and exposure to heat can also precipitate orthostatic hypotension and should be minimized. If dizziness, lightheadedness or palpitations occur, the patient should sit or lie down, and seek medical attention if symptoms are recurrent or bothersome.
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- "Product Information. Hytrin (terazosin)." Abbott Pharmaceutical, Abbott Park, IL.
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- "Product Information. Flomax (tamsulosin)." Boehringer-Ingelheim, Ridgefield, CT.
- Hardman JG, Gilman AG, Limbird LE eds. "Goodman and Gilman's the Pharmacological Basis of Therapeutics. 9th ed." New York, NY: McGraw-Hill (1995):
- Glass AR, Ballou R "Pheochromocytoma, prazosin, and hypotension." Ann Intern Med 97 (1982): 455
- Melkild A "Prazosin (peripress): a long-term study." Curr Med Res Opin 9 (1984): 219-28
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- Roehrborn CG, Siegel RL "Safety and efficacy of doxazosin in benign prostatic hyperplasia: a pooled analysis of three double-blind, placebo-controlled studies." Urology 48 (1996): 406-15
Prazosin (Includes Prazosin) ↔ Liver Disease
Moderate Potential Hazard, High plausibility
Applies to: Liver Disease, Biliary Obstruction
Little data exist concerning the pharmacokinetic disposition of prazosin in patients with liver disease. Prazosin is known to be metabolized by the liver and subsequently excreted in the bile, primarily as metabolites. Some of the metabolites are pharmacologically active and possess 10% to 25% of the hypotensive activity of prazosin. Therapy with prazosin should be administered cautiously in patients with significantly impaired hepatic or biliary function, since drug and/or metabolite accumulation may occur.
- Bateman DN, Rawlins MD "Prazosin concentration-effect, metabolism and biological activity of metabolites." Br J Clin Pharmacol 11 (1981): 221-
prazosin drug Interactions
There are 533 drug interactions with prazosin
prazosin alcohol/food Interactions
There is 1 alcohol/food interaction with prazosin
Drug Interaction Classification
|Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.|
|Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.|
|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.|
|No information available.|
Do not stop taking any medications without consulting your healthcare provider.
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