Medicines & Supplements A to Z > Silodosin


Last updated on 12/07/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  




DRUG CLASS: Vasodilators

SUB CLASS: Alpha blockers

USED FOR: Benign prostatic hyperplasia

AVAILABLE DOSAGE FORMS: 2 mg, 4 mg (capsules)

What is Silodosin for?

Silodosin belongs to a class of medications called alpha blockers. It is used to treat benign prostatic hyperplasia.

How to use it?

Silodosin can be taken by mouth. It should be taken with a meal.
If there is difficulty swallowing, you may sprinkle the contents of the capsule onto a tablespoon of applesauce, swallow immediately within 5 minutes without chewing with a glass of water.

Benign prostatic hyperplasia
8 mg once daily with a meal.

What are the side effects of Silodosin?

Common side effects of Silodosin include asthenia, diarrhoea, dizziness, dry mouth, headache, retrograde ejaculation, nasal congestion, postural hypotension, and insomnia.

Who should not take Silodosin?

– People allergic to Silodosin or any component of the formulation.
– Patients with reduced liver function or liver failure.
– Patients with severe kidney failure.
– Patients who are taking potent CYP3A4 inhibitors, e.g. Ketoconazole, Itraconazole, Ritonavir

Pharmacist Tips:

This medication can make you dizzy. Avoid driving or operating machinery until you know how you respond to Silodosin.

Common dosing schedule:
Silodosin should be taken once daily with a meal.

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Silodosin may interact with:
– Medicines for lowering blood pressure, e.g. Atenolol, Verapamil
– Potent CYP3A4 inhibitors, e.g. Ketoconazole, Itraconazole, Ritonavir
– Phosphodiesterase inhibitors, e.g. Sildenafil, Tadalafil, Vardenafil
Fluconazole, Probenecid, Valproic acid

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Silodosin has multiple significant drug interactions. Consult your doctor or pharmacist prior to taking any new medications, including over-the-counter, nutritional supplements, vitamins and herbal drugs.

Where to buy Silodosin in Hong Kong?

In Hong Kong, Silodosin is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Silodosin in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.