Tadalafil

PDE-5 inhibitor
PRESCRIPTION ONLY IN INDIA

Tadalafil is a pDE-5 inhibitor found in 12 medicines sold in India, such as Tadacip 20, Cialis 20, Megalis 20. Below: what it is for, how it works, how to take it, side effects, interactions and pregnancy advice.

What it is used for

Treats erectile dysfunction and, in daily low doses, an enlarged prostate.

How it works

A long-acting PDE-5 inhibitor (up to 36 hours) for erectile dysfunction and prostate symptoms.

How to take it

Either 10 to 20 mg before sex, or 2.5 to 5 mg daily. Not more than once a day.

Common side effects

  • Headache
  • Back or muscle pain
  • Flushing
  • Indigestion

Get medical help straight away if

  • Erection over 4 hours
  • Sudden vision or hearing loss
  • Chest pain

Be careful

Never take with nitrate heart medicines (dangerous drop in BP).

Other medicines and interactions

Never with nitrates or riociguat. Caution with alpha blockers and alcohol. Ritonavir, ketoconazole and clarithromycin raise levels.

Pregnancy and breastfeeding

Not relevant for erectile use.

Brands of Tadalafil (12)

Cialis 20Edalis 20Edgon 20Filda 20Forzest 20Megalis 20Tada 20Tadacip 20Tadact 20Tadovas 20Tazzle 20Upwardz 20

Common questions

What is Tadalafil used for?

Treats erectile dysfunction and, in daily low doses, an enlarged prostate.

How does Tadalafil work?

A long-acting PDE-5 inhibitor (up to 36 hours) for erectile dysfunction and prostate symptoms.

How should I take Tadalafil?

Either 10 to 20 mg before sex, or 2.5 to 5 mg daily. Not more than once a day.

What are the side effects of Tadalafil?

Common: Headache, back or muscle pain, flushing, indigestion. Get help straight away for: Erection over 4 hours, sudden vision or hearing loss, chest pain.

Does Tadalafil interact with other medicines?

Never with nitrates or riociguat. Caution with alpha blockers and alcohol. Ritonavir, ketoconazole and clarithromycin raise levels.

Is Tadalafil safe in pregnancy and breastfeeding?

Not relevant for erectile use.

Does Tadalafil need a prescription in India?

Yes. In India it is a prescription (Schedule H) medicine, so a pharmacist should sell it only with a doctor's prescription.

Which brands contain Tadalafil?

Cialis 20, Edalis 20, Edgon 20, Filda 20, Forzest 20, Megalis 20, Tada 20, Tadacip 20, Tadact 20, Tadovas 20, Tazzle 20, Upwardz 20.

Sources and further reading

NHS (UK National Health Service) and MedlinePlus (US National Library of Medicine) are free, reviewed medicine guides. Brand names and doses there may differ from India.

Last reviewed 31 October 2026. Written by Satya Babu from standard prescribing information.

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For information only, not medical advice. This page is a plain-language summary written from standard prescribing information and the public guides linked below. Brands sometimes change their formula, so always check the composition printed on the pack. Doses here are typical adult doses; yours may differ. Do not start, stop or change a medicine without your doctor or pharmacist, and keep all medicines away from children. In an emergency, call 112 (India) or your local emergency number.