Tamsulosin

What it is used for

• Symptoms of an enlarged prostate (benign prostatic hyperplasia), such as a weak flow and needing to pee often

Read our guides:

• Enlarged prostate (BPH)

Off-label uses

Doctors sometimes prescribe a medicine for a condition it is not officially licensed for. This is called off-label use. It is legal and common when there is good evidence it helps, and your doctor should explain why they are suggesting it.

• Helping kidney stones to pass
• Helping to pee again after a catheter is removed

How it works

Tamsulosin blocks alpha-1 receptors in the muscle of the prostate and bladder neck. This relaxes the muscle so urine flows more easily.

Side effects

Like all medicines, Tamsulosin can cause side effects, although not everyone gets them. Many are mild and ease after the first few weeks.

Common side effects

• dizziness when standing up
• problems with ejaculation
• a blocked or runny nose
• headache

Tell your doctor or pharmacist if these bother you or do not go away.

Serious side effects

These are rare. Call 111 or contact your doctor straight away if you get:

• fainting
• an erection lasting more than 4 hours
• a severe skin rash

Call 999 if you have signs of a serious allergic reaction, such as swelling of your lips, mouth, throat or tongue, or trouble breathing.

You can report any side effect to the Yellow Card scheme, run by the medicines regulator.

Stopping and withdrawal

Important safety information

• Tell the eye surgeon you take it before cataract surgery.
• Get up slowly from sitting or lying down.

Questions about your medicine?

A pharmacist can answer questions about your medicines for free, without an appointment. You can also ask your GP for a medication review. Check if you can get free prescriptions.