Can I take 12.5mg and Metformin together?
Drug interaction guide
Originally published 25 Jan 2026
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
- Language
- Discussion
There is no known interaction between sildenafil (the active ingredient in Viagra) and metformin. Both medications are commonly prescribed together for people with type 2 diabetes.
In this article:
Continue reading below
Why this happens
These drugs work in different ways and are processed by different systems in the body. Metformin helps control blood sugar levels, while sildenafil works on blood vessels to help with erectile dysfunction. They do not interfere with how the other is absorbed, used, or removed from the body.
What you should do
You can safely take these two medications together. However, because diabetes can affect your heart health and blood pressure, you should always ensure your doctor knows you are using sildenafil, as it can occasionally cause a slight drop in blood pressure.
Continue reading below
Using other medicines
Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
Patient picks for Drug interactions

Treatment and medication
Can I take Citalopram and Co codamol together?
Taking these two medicines together can increase the risk of a rare but serious condition called serotonin syndrome. It can also make you feel more drowsy or dizzy than usual. Additionally, citalopram may slightly reduce how well the codeine part of the co-codamol works to relieve your pain.

Treatment and medication
Can I take Idapamide and Ramipril together?
Taking indapamide and ramipril together can cause your blood pressure to drop too low, especially when you first start the combination. This can make you feel dizzy, lightheaded, or faint. It can also put extra strain on your kidneys.
Continue reading below
Article history
The information on this page is written and peer reviewed by qualified clinicians.
25 Jan 2026 | Originally published

Ask, share, connect.
Browse discussions, ask questions, and share experiences across hundreds of health topics.

Feeling unwell?
Assess your symptoms online for free
Sign up to the Patient newsletter
Your weekly dose of clear, trustworthy health advice - written to help you feel informed, confident and in control.
By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.