Silodosin

What is Silodosin?

• Silodosin (Rapaflo) an alpha-1 adrenergic receptor antagonist used for the symptomatic treatment of benign prostatic hyperplasia (BPH).

Silodosin

Silodosin Structural Formula V.1

What are the uses of this medicine?

• Silodosin (Rapaflo) is used for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH).

Limitations of use:

• RAPAFLO is not indicated for the treatment of hypertension.

How does this medicine work?

• Silodosin is a selective antagonist of post-synaptic alpha-1 adrenoreceptors, which are located in the human prostate, bladder base, bladder neck, prostatic capsule, and prostatic urethra.
• Blockade of these alpha-1 adrenoreceptors can cause smooth muscle in these tissues to relax, resulting in an improvement in urine flow and a reduction in BPH symptoms.

Who Should Not Use this medicine ?

This medicine cannot be used in patients with:

• severe renal impairment.
• severe hepatic impairment.
• Concomitant administration with strong Cytochrome P450 3A4 (CYP3A4) inhibitors (e.g., ketoconazole, clarithromycin, itraconazole, ritonavir).

What drug interactions can this medicine cause?

• Concomitant administration of strong CYP3A4 inhibitors (e.g., itraconazole, clarithromycin, ritonavir) and RAPAFLO is contraindicated.
• RAPAFLO is not recommended in patients taking strong P-gp inhibitors such as cyclosporine.
• RAPAFLO should not be used in combination with other alpha-blockers.
• Concomitant administration of RAPAFLO and digoxin did not significantly alter the steady state pharmacokinetics of digoxin. No dose adjustment is required.
• Concomitant use of PDE5 inhibitors with alpha-blockers including Rapaflo can potentially cause symptomatic hypotension.

Is this medicine FDA approved?

* The United States Food and Drug Administration and Health Canada approved silodosin under the brand name Rapaflo on 9 October 2008 and 11 January 2011, respectively.

How should this medicine be used?

Recommended dosage:

• 8 mg capsules taken orally once daily with a meal.
• 4 mg capsules taken orally once daily with a meal for those with moderate renal impairment.

Administration:

• Patients should be instructed to take RAPAFLO once daily with a meal.

What are the dosage forms and brand names of this medicine?

This medicine is available in fallowing doasage form:

• As Capsules: 8 mg and 4 mg

This medicine is available in fallowing brand namesː

• RAPAFLO

What side effects can this medication cause?

The most common side effects of this medicine include:

• retrograde ejaculation
• dizziness
• diarrhea
• orthostatic hypotension
• headache
• nasopharyngitis
• nasal congestion

What special precautions should I follow?

• Postural hypotension, with or without symptoms (e.g., dizziness), may develop when beginning RAPAFLO treatment. Patients should be cautioned about driving, operating machinery, or performing hazardous tasks when initiating therapy.
• In patients with moderate renal impairment, RAPAFLO dose should be reduced to 4 mg once daily. Exercise caution and monitor such patients for adverse events. RAPAFLO is contraindicated in patients with severe renal impairment.
• RAPAFLO should not be used in combination with other alpha-blockers.
• Carcinoma of the prostate and BPH cause many of the same symptoms. These two diseases frequently co-exist. Examine patients thought to have BPH prior to starting therapy with RAPAFLO to rule out the presence of carcinoma of the prostate.
• Inform patients planning cataract surgery to notify their ophthalmologist that they are taking RAPAFLO because of the possibility of Intraoperative Floppy Iris Syndrome (IFIS).
• RAPAFLO has not been tested in patients with severe hepatic impairment, and therefore, should not be prescribed to such patients.

What to do in case of emergency/overdose?

Symptoms of overdosage may include:

• postural hypotension

Management of overdosage:

• Restoration of blood pressure and normalization of heart rate may be accomplished by maintaining the patient in the supine position.
• If this measure is inadequate, administration of intravenous fluid should be considered.
• If necessary, vasopressors could be used, and renal function should be monitored and supported as needed.
• Dialysis is unlikely to be of significant benefit since silodosin is highly (97%) protein bound.

Can this medicine be used in pregnancy?

• Pregnancy Category B.
• RAPAFLO is not indicated for use in women.

Can this medicine be used in children?

• RAPAFLO is not indicated for use in pediatric patients.
• Safety and effectiveness in pediatric patients have not been established.

What are the active and inactive ingredients in this medicine?

Active ingredient:

• SILODOSIN

Inactive ingredients:

• none

Who manufactures and distributes this medicine?

Manufactured by: Watson Laboratories, Inc. Corona, CA USA

Distributed by:

• Watson Pharma, Inc.
• Parsippany, NJ USA

What should I know about storage and disposal of this medication?

• Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F).
• Protect from light and moisture.

• Dailymed label info on Silodosin
• FDA Silodosin