Nihonbashi ClinicMetformin hydrochloride · Oral medicine
Metformin
Online consultation
An oral medicine for glucose metabolism. Weight-loss use is off-label.
Discuss an oral option for medical weight management, with a review of your health history and kidney function. English phone consultations and domestic delivery are available.
From ¥5,000 including tax
Consultation with purchase ¥0 · Standard delivery within Japan ¥0
Prices and what you pay
| Medicine & quantity | Total with purchase |
|---|---|
| 250 mg · 90 tablets | ¥5,000 |
| 500 mg · 60 tablets | ¥6,000 |
| 500 mg · 90 tablets | ¥9,000 |
All prices include tax. With a medicine purchase, the consultation fee is ¥0 and standard domestic delivery is currently ¥0. No single-injection-pen handling fee applies to these oral medicines. The listed total assumes this medicine and quantity only; additional medicines or documents cost extra.
If you complete the consultation and choose not to purchase medicine, the consultation fee is ¥3,000. If questionnaire review ends without a consultation being carried out, there is no consultation fee. See full fee conditions.
Payment: credit card or bank transfer. For instalment options, check with your card provider. The doctor determines whether to prescribe, the dose and the quantity.
About Metformin
Metformin reduces glucose production in the liver and improves insulin sensitivity. It is used for type 2 diabetes; Japanese product indications can also include selected polycystic ovary syndrome treatment. Weight management is off-label. This page concerns our self-pay medical diet service, not fertility treatment.
Research and expectations
The UKPDS 34 study involved overweight people with type 2 diabetes and found lower diabetes-related outcomes and mortality compared with conventional treatment. Those findings are not a promise of cardiovascular protection in a person without diabetes. In the Diabetes Prevention Program, metformin reduced progression to diabetes by 31% versus placebo in a high-risk population over about three years; this is a relative reduction, not a weight-loss percentage. Ageing research, including the TAME proposal, explores a further question. It does not demonstrate that this prescription makes people younger or extends their lifespan.
Taking the medicine
Take the prescribed amount with the meal timing specified by your doctor. The clinic offers 250 mg and 500 mg tablets. Tablet count alone does not determine the appropriate daily dose; do not increase it yourself.
Side effects and precautions
Diarrhoea, nausea and abdominal discomfort can occur. Rare lactic acidosis is serious. Severe kidney impairment (eGFR below 30) or dialysis, dehydration, severe liver disease, hypoxic illness and excessive alcohol intake are important contraindications. Discuss pregnancy, surgery, contrast scans and acute illness in advance. Severe weakness, vomiting or breathing difficulty warrants urgent medical assessment.
Tell us about all prescriptions, supplements and allergies. This overview does not replace the information supplied with your medicine. For non-urgent questions, contact our official LINE. For an emergency in Japan, call 119.
From booking to delivery
Book online
Choose an appointment. For a first consultation, provide identification and complete the questionnaire as instructed.
Phone consultation
The doctor calls your registered number. Discuss your goals, health history, medicines and questions in English. A prescription is not guaranteed.
Payment and delivery
After the consultation and payment, dispatch is normally within 2–3 business days, or up to 7 when busy. This is a dispatch estimate, not an arrival guarantee. Delivery is within Japan only.
Oral medicines are generally sent by domestic post. With Click Post, the parcel goes to your letterbox and a delivery-time appointment cannot be selected. Check your delivery address before payment.
A formal English medical letter costs ¥5,000 if requested; a printed receipt is free. Requirements for taking medicine abroad depend on the destination. A letter does not guarantee import permission.
Your questions, answered
Who should discuss metformin?
Tell the doctor about your weight goals, glucose results, kidney function and previous treatment. A lower price or preference for an oral medicine does not make it suitable for everyone.
How much weight will I lose?
Responses vary, and weight loss is not guaranteed. The research on diabetes prevention and diabetes complications answers different questions from cosmetic weight loss. Food habits and activity remain part of the discussion.
Can I combine it with other treatment?
Discuss Mounjaro, Rybelsus, Lusefi or other medicines with the doctor rather than adding them yourself. The overall prescription and risk of reduced food intake, dehydration or low glucose need review.
Can I take it with reduced kidney function?
Recent renal blood tests help determine suitability and dosing. An eGFR below 30 is a contraindication, not simply a reason to lower the dose. Additional monitoring or an in-person assessment may be required.
What if I have diarrhoea or cannot eat?
Contact the clinic for advice about temporary interruption and recovery. Seek urgent care for severe symptoms. Avoid excessive alcohol and tell any treating clinician that you take metformin.
Does it have an anti-ageing effect?
This is a research topic, not an established benefit of our treatment. We do not prescribe a promised lifespan extension or rejuvenation outcome.
Medicine information and sources
Metformin products are approved medicines in Japan, but use for weight management is off-label. Medicines are sourced through authorised Japanese wholesalers. The reference below is the Metgluco label for the ingredient; the dispensed manufacturer may differ. Wegovy and Zepbound have specific Japanese obesity indications and eligibility requirements. Overseas approval does not automatically apply to this use. Off-label treatment may fall outside Japan’s adverse drug reaction relief scheme.
PMDA prescribing information (Japanese) · Japanese clinic page
UKPDS 34 · NIDDK: Diabetes Prevention Program · TAME research rationale
Information checked: 12 October 2026. The doctor assesses suitability individually.