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Flomax (tamsulosin) Disease Interactions

There are 4 disease interactions with Flomax (tamsulosin):

Major

Alpha-1 Blockers (Includes Flomax) ↔ Hypotension

Severe Potential Hazard, Moderate plausibility

Applies to: Autonomic Neuropathy, Hypotension, Syncope, 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.

References

  1. "Product Information. Cardura (doxazosin)." Pfizer US Pharmaceuticals, New York, NY.
  2. Graham RM, Thornell IR, Gain JM, Bagnoli C, Oates HF, Stokes GS "Prazosin: the first-dose phenomenon." Br Med J 2 (1976): 1293-4
  3. "Prazosin (Minipress) for hypertension." Med Lett Drugs Ther 19 (1977): 1-2
  4. Troffa C, Manunta P, Dessifulgheri P, Pazzola A, Sabino G, Patteri G, Tonolo G, Pupita G, Glorioso N, Gitti M, Rappelli A "Efficacy and tolerability of doxazosin alone or in combination with chlorthalidone in essential hypertension." Curr Ther Res Clin Exp 55 (1994): 22-31
  5. Takata Y, Yoshizumi T, Ito Y, Hirota Y, Fujishima M "Effect of administration and withdrawal of doxazosin on ambulatory blood pressure in patients with essential hypertension." Angiology 46 (1995): 11-8
  6. "Product Information. Hytrin (terazosin)." Abbott Pharmaceutical, Abbott Park, IL.
  7. Grunstein JA "The problem of postural hypotension." Gerontol Clin (Basel) 16 (1974): 171-4
  8. "Product Information. Flomax (tamsulosin)." Boehringer-Ingelheim, Ridgefield, CT.
  9. Ahaneku JE, Taylor OG, Walker D, Agbedana OE, Salako LA "Blood pressure and biochemical changes during doxazosin monotherapy in nigerian hypertensive patients." Curr Ther Res Clin Exp 55 (1994): 1067-74
  10. Hardman JG, Gilman AG, Limbird LE eds. "Goodman and Gilman's the Pharmacological Basis of Therapeutics. 9th ed." New York, NY: McGraw-Hill (1995):
  11. Glass AR, Ballou R "Pheochromocytoma, prazosin, and hypotension." Ann Intern Med 97 (1982): 455
  12. Melkild A "Prazosin (peripress): a long-term study." Curr Med Res Opin 9 (1984): 219-28
  13. 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
  14. Salim SS, Mtui EP, Makene WJ "An open evaluation of the efficacy and toleration of prazosin in patients with hypertension." East Afr Med J 54 (1977): 429-33
View all 14 references
Major

Tamsulosin (Includes Flomax) ↔ Glaucoma

Severe Potential Hazard, Moderate plausibility

Applies to: Glaucoma/Intraocular Hypertension, Cataracts

Intraoperative Floppy Iris Syndrome (IFIS) has been observed during cataract and glaucoma surgery in some patients on or previously treated with alpha 1 blockers, including tamsulosin. The initiation of therapy with tamsulosin in patients for whom cataract or glaucoma surgery is scheduled is not recommended. The patient's ophthalmologist should be aware if the patient is receiving treatment with this drug and should be prepared for possible modifications to the surgical technique, such as the utilization of iris hooks, iris dilator rings, or viscoelastic substances.

Moderate

Tamsulosin (Includes Flomax) ↔ End-Stage Renal Disease

Moderate Potential Hazard, Moderate plausibility

Applies to: Renal Dysfunction

Patients with renal impairment do not require an adjustment in tamsulosin dosing. However, patients with end-stage renal disease (Clcr <10 mL/min) have not been studied.

Moderate

Tamsulosin (Includes Flomax) ↔ Severe Liver Disease

Moderate Potential Hazard, Moderate plausibility

Applies to: Liver Disease

Patients with moderate hepatic impairment do not require any adjustment in tamsulosin dosage. Tamsulosin has not been studied in patients with severe hepatic impairment.

Flomax (tamsulosin) drug Interactions

There are 508 drug interactions with Flomax (tamsulosin)

Flomax (tamsulosin) alcohol/food Interactions

There are 2 alcohol/food interactions with Flomax (tamsulosin)

Drug Interaction Classification

The classifications below are a general guideline only. It is difficult to determine the relevance of a particular drug interaction to any individual given the large number of variables.
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 information available.

Do not stop taking any medications without consulting your healthcare provider.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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