Key facts

  • ED is common and treatable, and becomes more common with age, so an occasional off night is normal and a persistent problem is worth looking into.
  • Persistent ED can be an early warning sign of heart or circulation problems, so the first step is a doctor who can check your blood pressure and general health, not a shortcut.
  • The usual medicines are PDE-5 inhibitors: sildenafil (Viagra), tadalafil (Cialis), vardenafil (Levitra) and avanafil (Spedra). They are prescription medicines, and whether one suits you is a clinician’s decision.
  • Never combine a PDE-5 inhibitor with nitrate heart medicines (used for angina); the combination can drop blood pressure to dangerous levels. Tell any doctor about every medicine you take.
  • Find the medicine by its active ingredient, not the brand, because the local name in Thailand is often different.
  • ED medicines are among the most counterfeited products in the world, so buy only from a licensed pharmacy or legitimate source, never a market stall, bar or spam email.

Why does ED happen, and why can it be a health signal?

A recurring erection problem can have a physical cause, a psychological cause or both. The NHS calls ED common, particularly after 40, and says most men occasionally have trouble after stress, tiredness or too much alcohol. Treatment usually helps. A problem that keeps happening is different: it deserves a health check even if erections still happen at other times, such as on waking.

The NHS lists high blood pressure, high cholesterol, diabetes, depression, anxiety and hormone problems among possible causes of frequent ED. Medicines themselves can also be involved. The circulation link matters: the blood-vessel changes affecting erections may be an early sign of a cardiovascular problem elsewhere.

A clinician may ask about lifestyle, relationships and medicines, take your blood pressure and examine you for an obvious physical cause. Blood sugar and general health may also need checking. The point of the consultation is to find a suitable treatment and notice any condition that needs care in its own right; embarrassment need not delay it.

What are the common treatments for ED?

For most men the first-line treatment is a group of prescription medicines called PDE-5 inhibitors, which improve blood flow to the penis when you are aroused. They are effective, but they are still medicines with real safety points, so whether one is right for you is a clinician’s decision.

The NHS lists the familiar ones: sildenafil (the active ingredient in Viagra), tadalafil (Cialis), vardenafil (Levitra) and avanafil (Spedra). They differ mainly in how quickly they work and how long the effect lasts, which is part of why a clinician helps you match one to your situation.

The most important safety point deserves stating plainly: PDE-5 inhibitors can be dangerous when combined with nitrate medicines used for heart conditions such as angina, because the combination can drop blood pressure to unsafe levels. The NHS guidance on sildenafil and on tadalafil sets out who should not take them and what to check first. Whether one is right for you, and at what dose, depends on your health and your other medicines, so this is a clinician’s decision rather than a guess. We do not give dosing here for that reason.

How do I find ED medicine by active ingredient?

Read the active ingredient, not the brand, because the local name in Thailand is often different. Viagra is sildenafil and Cialis is tadalafil, and both exist widely as generics, the same active ingredient as the familiar brand without the brand price.

Our active ingredient pages group the brands that share a molecule, so you can recognise sildenafil or tadalafil wherever you are, and the erectile dysfunction category gathers the options, including vardenafil and avanafil, in one place. Knowing the ingredient also makes it far easier to tell a genuine product from a fake. If you want the brand-specific picture, our guides to Viagra in Thailand and Kamagra in Thailand go into the local products and their pitfalls.

How do I avoid counterfeit ED medicine in Thailand?

Buy only from a licensed pharmacy or a legitimate source, never a market stall, a bar or a spam email. ED medicines are among the most counterfeited products in the world, and a fake can contain the wrong dose, the wrong drug or contaminants, which is genuinely risky with a medicine that affects blood pressure. The World Health Organization estimates that around one in ten medical products in low- and middle-income countries is substandard or falsified.

The WHO distinguishes a substandard product, which fails quality standards, from a falsified one, whose identity, composition or source is deliberately misrepresented. Both may reach buyers through informal markets or unregulated websites. In Thailand, that makes a tourist-area stall, a bar, a street vendor or a spam email a poor place to find an ED medicine, however discreet or cheap the offer seems. Check the active ingredient and strength, use a proper pharmacy, and read our guide to buying medicine in Thailand for the wider checks. If you order a non-urgent refill online, check who dispenses it, where the pharmacy is licensed and how it handles a prescription medicine.

ZoneMD option: After a clinician has confirmed a PDE-5 inhibitor is suitable, you can search by active ingredient and compare available brands and generics for an ongoing supply. Licensed pharmacy partners handle dispensing and delivery; how ordering works sets out the steps. A local pharmacy may be more convenient, while delivery may be more discreet where you live.

When should I see a doctor?

See a doctor rather than self-treating if:

  • Erection problems keep happening, rather than being the occasional off night.
  • You have not had your blood pressure, blood sugar or general health checked recently, since ED can be an early signal.
  • You take nitrate medicines for your heart, or any other regular medicine, before starting a PDE-5 inhibitor.
  • ED comes on with other symptoms, or is causing you real distress or relationship strain.

A doctor can treat the ED and check the bigger picture at the same time, which is the whole point.

Do and don’t

Do:

  • See a doctor for a persistent problem, both to treat it and to check your heart and general health.
  • Tell any doctor or pharmacist about every medicine you take, especially heart medicines.
  • Find the medicine by its active ingredient and strength, not just the brand name.
  • Buy from a licensed pharmacy or legitimate source, and check the pack is sealed with a clear batch number and expiry.
  • Ask a pharmacist if you are unsure which local product matches your medicine.

Don’t:

  • Combine a PDE-5 inhibitor with nitrate heart medicine; the blood-pressure drop can be dangerous.
  • Buy from a market stall, bar, street vendor or spam email, regardless of how familiar the pack looks.
  • Ignore a persistent problem because it is embarrassing, or guess at a dose without clinical advice.

What should I check next?

See a clinician if ED keeps happening, then check the active ingredient and the source of any medicine you receive. Browse by active ingredient or the erectile dysfunction category. The ordering and delivery guide and medicine-buying guide for Thailand explain the practical side.

This guide is general information, not medical advice. Whether a treatment is right and safe for you is a decision for a doctor or pharmacist who knows your health.