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Below are the general guidelines for dosing tamsulosin (Flomax). Note that these dosages may be adjusted on a case-by-case basis for individual patients. Always follow your prescribing physician’s instructions for taking tamsulosin.

The following information comes from DailyMed, an FDA label information provider.

What if I miss a dose of tamsulosin?

According to Mayo Clinic, if you miss a dose of tamsulosin, take the missed dose immediately unless you are closer in time to your next dose. Never double doses.

What if I overdose on tamsulosin?

**If you believe you or someone you know has overdosed, call 911 immediately for medical assistance.

Should overdosage of tamsulosin hydrochloride capsules lead to hypotension [see WARNINGS AND PRECAUTIONS (5.1) and ADVERSE REACTIONS (6.1)], support of the cardiovascular system is of first importance. Restoration of blood pressure and normalization of heart rate may be accomplished by keeping the patient in the supine position. If this measure is inadequate, then administration of intravenous fluids should be considered. If necessary, vasopressors should then be used and renal function should be monitored and supported as needed. Laboratory data indicate that tamsulosin hydrochloride is 94% to 99% protein bound; therefore, dialysis is unlikely to be of benefit.

Dosage and Administration

Tamsulosin hydrochloride capsules 0.4 mg once daily is recommended as the dose for the treatment of the signs and symptoms of BPH. It should be administered approximately one-half hour following the same meal each day. Tamsulosin hydrochloride capsules should not be crushed, chewed or opened.

For those patients who fail to respond to the 0.4 mg dose after 2 to 4 weeks of dosing, the dose of tamsulosin hydrochloride capsules can be increased to 0.8 mg once daily. Tamsulosin hydrochloride capsules 0.4 mg should not be used in combination with strong inhibitors of CYP3A4 (e.g., ketoconazole) [see WARNINGS AND PRECAUTIONS (5.2)].

If tamsulosin hydrochloride capsules administration is discontinued or interrupted for several days at either the 0.4 mg or 0.8 mg dose, therapy should be started again with the 0.4 mg once-daily dose.

How is tamsulosin supplied?

Tamsulosin hydrochloride capsules USP, 0.4 mg are supplied in high density polyethylene bottles containing 30 or 500 size ‘2’, hard gelatin capsules with olive green opaque cap and orange opaque body, filled with white to off-white pellets. The capsules are imprinted with “W” on the cap with black ink.                    

Tamsulosin hydrochloride capsules USP, 0.4 mg, 30 capsules (NDC 64679-516-01)

Tamsulosin hydrochloride capsules USP, 0.4 mg, 500 capsules (NDC 64679-516-03)

Store at 20° to 25°C (68°C to 77°F) [See USP Controlled Room Temperature].

Keep tamsulosin hydrochloride capsules, USP and all medicines out of reach of children.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.


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