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Sildenafil in Japan: ED Treatment, Directions and Safety
This guide to Sildenafil in Japan covers ED treatment, food and medicine interactions and cardiovascular safety. It separates medicine-specific information from the product and prescription checks needed for an individual consultation.
This page explains how Sildenafil works, its directions, limitations and safety. For prices and individual prescriptions, see SWIFT’s relevant care information.
Sildenafil is a PDE5 inhibitor that supports erections in response to sexual stimulation. It does not increase sexual desire, and combining it with nitrates is dangerous. Check meals, other medicines and cardiovascular status before use.
Medical reviewer: Masashi Morita, MD
Sildenafil is a PDE5 inhibitor that supports erections in response to sexual stimulation. It does not increase sexual desire, and combining it with nitrates is dangerous. Check meals, other medicines and cardiovascular status before use.
- Ingredient/class
- Sildenafil citrate
- Eligible patients/indications
- This article concerns formulations for ED. The same ingredient is also used in pulmonary arterial hypertension products, but their indications and directions differ and must not be repurposed. Assess whether diabetes, vascular disease, medicines or psychological factors underlie ED.
- Assessing effects
- Time to response varies between individuals and may be delayed by food. The time to a high blood concentration is not the same as the time for satisfactory intercourse. An erection does not remain continuous throughout the period of action.
- Clinic care
- Service information supported by public sources is identified in the article. Final prescribing decisions are made during consultation.
What the medicine is
It inhibits PDE5, which breaks down cGMP in the corpus cavernosum, supporting blood-flow changes caused by sexual stimulation. It does not automatically produce an erection without stimulation. Viagra is a brand name; sildenafil is the ingredient name.
Eligible patients and approved indications
This article concerns formulations for ED. The same ingredient is also used in pulmonary arterial hypertension products, but their indications and directions differ and must not be repurposed. Assess whether diabetes, vascular disease, medicines or psychological factors underlie ED.
Source: Medicine-specific primary documentation. The product used by the clinic is not assumed to be identical to the formulation in this documentation.
Treatment limitations and when diagnosis is needed
Responses vary with insufficient stimulation, taking it after food, tension and alcohol. Do not increase the dose or combine another ED medicine after a single unsuccessful attempt. It does not directly treat premature ejaculation or reduced libido.
Formulations and basic directions
The approved Japanese directions for ED tablets in adults are 25–50 mg approximately 1 hour before intercourse, no more than once daily and at least 24 hours apart. Starting doses are lowered depending on older age and liver or kidney function. Food may delay absorption; plan timing according to the prescriber’s instructions. Check the actual clinic product separately.
Source: Medicine-specific primary documentation. The product used by the clinic is not assumed to be identical to the formulation in this documentation.
Timing of response and decisions about continuation
Time to response varies between individuals and may be delayed by food. The time to a high blood concentration is not the same as the time for satisfactory intercourse. An erection does not remain continuous throughout the period of action.
Side effects and symptoms to watch for
Reported reactions include headache, flushing, nasal congestion, indigestion, palpitations and visual changes. Also watch for low blood pressure, prolonged erection and sudden vision or hearing abnormalities.
Source: Medicine-specific primary documentation. The product used by the clinic is not assumed to be identical to the formulation in this documentation.
When to stop and seek medical attention
For chest pain, severe breathing difficulty or fainting, stop sexual activity and seek emergency care. Tell the clinician you took sildenafil. Do not use nitroglycerin or similar medicines yourself. An erection lasting 4 hours or more or sudden vision loss requires immediate assessment.
Restrictions and interactions
Nitrates/NO donors (including nitroglycerin and nicorandil) and riociguat are contraindicated combinations. Concomitant use with oral amiodarone hydrochloride is also contraindicated. Use may also be prohibited with cardiovascular disease making sexual activity inadvisable, recent myocardial infarction or stroke, or serious liver impairment. Disclose alpha blockers, antihypertensives and HIV medicines, and do not combine other ED medicines.
Source: Medicine-specific primary documentation. The product used by the clinic is not assumed to be identical to the formulation in this documentation.
Pregnancy, breastfeeding and patient precautions
This ED treatment is intended for adult men. Do not give it to a partner or anyone other than the person prescribed it.
Additional care
Review meals, alcohol amounts, sleep and dosing time, and discuss effects and side effects. Do not add a dose if excessive alcohol reduces the effect.
Storage and quality checks
Follow the product label and store in the original packaging away from moisture and high temperatures. Check actual clinic-product storage conditions and expiry on its label.
Differences from other medicines and treatments
Tadalafil differs in duration of action and food effects; vardenafil carries QT-prolongation precautions. Choose according to everyday timing, medical history and other medicines rather than a simple strength ranking.
Discussing consultation and prescribing with SWIFT
The official ED page lists sildenafil formulations. The existing medicine landing page records Gentle-V 50 mg at JPY 830 per tablet, but this product must not be equated with Japanese-approved Viagra or Japanese generics. Prices, Japanese approval status, sourcing and adverse-reaction relief-system information require final reconciliation with current clinic information.
Our clinic’s ED care and product information for further information. Confirm approval status, sourcing and conditions during consultation; do not assume the same conditions as Japanese-approved products.
Frequently asked questions
For Sildenafil, does it differ from Viagra?
Viagra is a brand containing sildenafil. Even with the same ingredient, check the formulation and Japanese approval status.
For Sildenafil, can I take it after a meal?
Food may delay absorption. Do not add a dose for a weak response after eating; discuss conditions for the next dose with a doctor.
For Sildenafil, can I take two tablets if it does not work?
Do not increase the dose yourself. Combining doses may increase side effects and blood-pressure reductions.
Medical supervision
Dr Masashi Morita (Board-certified specialist and supervising physician, Japanese Urological Association / Board-certified specialist, Japan Endocrine Society / Doctor of Medical Science).
References
Book a sildenafil consultation
The booking page opens with Viagra selected, the sildenafil treatment item. The doctor determines the actual medicine and dose after consultation.