Flomax

Flomax Generic Name

Tamsulosin hydrochloride is the generic name for the brand Flomax. This medication belongs to a class of drugs known as alpha-blockers.

Therapeutic Indications

Flomax is primarily indicated for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH) in men. This condition is also known as an enlarged prostate. It is not indicated for the treatment of hypertension.

Pharmacological Action

Flomax works by selectively blocking alpha1-adrenergic receptors in the prostate, bladder neck, and urethra, which leads to relaxation of smooth muscle in these areas and an improvement in urine flow.

Dosage Forms Available

The medication is available in capsule form for oral administration, typically in 0.4 mg strength.

Recommended Dosage

The usual starting dose of Flomax is 0.4 mg once daily, approximately 30 minutes after the same meal each day. Based on individual response and tolerability, the dosage may be increased to 0.8 mg once daily.

Dosage Adjustments

For patients with moderate to severe renal impairment (creatinine clearance 10 to 70 mL/min), the dose should be adjusted with caution but remains the same starting dose. Flomax has not been studied in patients with severe hepatic impairment.

Administration Instructions

Flomax capsules should not be crushed, chewed, or opened. They must be swallowed whole to ensure the controlled release of the medication. Take the capsule one-half hour following the same meal each day.

Drug Interactions

Concomitant use with other alpha-adrenergic blocking agents may enhance the hypotensive effect. Use with strong inhibitors of CYP3A4 (e.g., ketoconazole) may lead to an increase in Flomax concentrations. Flomax should not be used in combination with other inhibitors of CYP2D6 if avoidable.

Missed Dose Management

If a dose of Flomax is missed, take the dose as soon as possible. If it is almost time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not double doses.

Important Precautionary Measures

Flomax can cause a drop in blood pressure when going from a sitting to a standing position, known as orthostatic hypotension. Patients should be cautioned about this potential problem and advised to avoid situations where injury could result should syncope occur.

Potential Side Effects

Common side effects include dizziness, headache, abnormal ejaculation, and runny or stuffy nose. Less common side effects may include priapism, a prolonged and painful erection requiring immediate medical attention.

Considerations for Special Populations

Flomax is not approved for use in women and children. Men with a history of orthostatic hypotension or with concomitant administration of other alpha-blockers may be at increased risk of hypotension.

Overdose Management

In case of overdose, cardiovascular support should be provided. Blood pressure can be lowered by lying down, and if necessary, volume expanders can be administered to combat hypotension. Dialysis is unlikely to be helpful as Flomax is highly bound to plasma proteins.

Storage Conditions

Flomax should be stored at room temperature, away from moisture and heat. Keep the capsules in their original container and out of reach of children.

Discontinuation of Use

If Flomax therapy is discontinued for several days at either the 0.4 mg or 0.8 mg dose, therapy should be restarted with the 0.4 mg once daily dose.

Flomax Monitoring Parameters

Regular monitoring of blood pressure and prostate-specific antigen (PSA) levels is recommended during treatment with Flomax. Monitor for signs and symptoms of orthostatic hypotension.

Effect on Pupil Size

Flomax can cause intraoperative floppy iris syndrome (IFIS) during cataract surgery. Patients planning cataract surgery should inform their ophthalmologist of current or past use of Flomax.

Pharmacist’s Role in Patient Education

Pharmacists should counsel patients on the proper use and potential side effects of Flomax, emphasizing the need to take it 30 minutes after the same meal each day and not to crush or chew the capsule. Additionally, patients should be informed about the possibility of dizziness and advised on precautions to avoid injury from falls or accidents.