Yes, you can go out in the sun while taking metformin. For most people, metformin will not make you more sensitive to sunlight.  

There have been a few rare cases of people taking metformin having a rash after being in the sun. Contact your doctor if you notice any skin changes or rashes after starting metformin.  

Regardless of the medicines you take, use caution when going out in the sun. Protect your skin from the harmful effects of the sun’s UV rays. Use sunblock, hats, and stay in the shade. 

Metformin and sun are ok, but wear sunblock if you go out and play! 

block the rays