Private ED care · Bangkok

Sildenafil for ED: timing, effects and options in Bangkok

Understand the ingredient behind Sidegra and Viagra, including timing and food effects.

The short answer

Sildenafil is the active ingredient in Sidegra and Viagra. It helps erections in response to sexual stimulation and is generally used when needed. Kauri offers Sidegra 50 mg, Sidegra 100 mg and Viagra 100 mg.

Available packs and prices at Kauri

ED medication packs at Kauri Health Clinic
ProductActive ingredientStrength per tabletTablets per packPack price (THB)
Sidegra 50 mgSildenafil50 mg4฿250
Sidegra 100 mgSildenafil100 mg4฿450
Viagra 100 mgSildenafil100 mg4฿2,100

How does sildenafil work?

Sildenafil blocks the PDE5 enzyme, helping preserve the signal that relaxes blood vessels during sexual arousal. That supports blood flow into the penis. It treats the erection response rather than the desire for sex. It is one established oral treatment for ED; the most useful choice depends on the person and the causes of their symptoms.

How fast does sildenafil work?

Many people plan sildenafil around 1 hour before sex. Its response window usually lasts several hours, commonly around 4 hours, with variation between individuals. A large or fatty meal can delay the onset, so the same dose may seem slower after eating. Stimulation is needed; waiting for an automatic erection can make an otherwise suitable treatment seem ineffective.

Which strengths and brands are available at Kauri?

Our current menu includes Sidegra 50 mg and 100 mg, and Viagra 100 mg. A physician chooses the dose rather than using the pack strength as a starting recommendation. Kidney or liver problems and interacting medicines can change the appropriate dose. Sildenafil and tadalafil doses cannot be compared milligram-for-milligram.

What if sildenafil is not helping?

A review can check whether the medicine was taken as directed, whether enough time and stimulation were allowed, and whether meals or alcohol affected the experience. Persistent ED can also reflect circulation, diabetes, medications or emotional factors. Kauri can review relevant testing, another oral treatment or specialist referral. Increasing the dose yourself can add side effects without solving the cause.

Side effects: what should I know?

ED tablets are well tolerated by many patients. Headache, flushing, indigestion, nasal congestion and dizziness can occur. Sildenafil may cause temporary visual changes; tadalafil may cause back or muscle aches. Tell Kauri about troublesome effects so your treatment can be reviewed.

Who needs a medication review first?

Never combine these medicines with nitrates, poppers or riociguat. Tell your physician about heart symptoms, low blood pressure, kidney or liver conditions, eye problems and all other medicines, including alpha-blockers. Do not combine ED tablets yourself. Seek urgent care for an erection lasting 4 hours or longer, sudden vision or hearing loss, or chest pain; tell the treating team what you took and when. Do not self-administer nitrates after an ED medicine.

Private ED care at BTS Punnawithi, Bangkok

At Kauri, we review your symptoms, current medicines, previous response and preferences, then explain suitable treatment and follow-up. Relevant blood testing or specialist referral can be arranged when needed. Visit Kauri Health Clinic at BTS Punnawithi, 3063 Sukhumvit Rd, Bang Chak, Phra Khanong, Bangkok 10260. We are open Tuesday–Saturday, 9:00–18:00, and closed Sunday and Monday.

Patient questions

Sildenafil guide: frequently asked questions

Is sildenafil the same as Viagra?

Sildenafil is the ingredient. Viagra and Sidegra are brands containing it. Compare the prescribed strength and pack size as well as the brand and price.

Does sildenafil increase testosterone?

No. Sildenafil supports erection-related blood flow. Low testosterone and reduced sexual desire require a separate assessment when symptoms suggest a hormone concern.

Can I take another dose on the same day?

The maximum recommended dosing frequency for sildenafil is once daily. Follow your prescription, which may set a lower dose or a longer interval. Do not add a second ED medicine.

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Medication and comparison guides

Start with a medicine you know, or compare the ingredients and treatment patterns.

Medical sources

Medicine information draws on public clinical guidance. Pack details and prices are supplied by Kauri. Content updated 16 October 2026.

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