I found a pill it has G 31 on it other side has line pill is white

Question

I found a pill it has G 31 on it other side has line pill is white

Answer 1

Is it round, oval, or square?  Is it smooth, solid white, or does it have flecks?  Is it large or small?  Does it have any other markings?  It will be VERY difficult for anyone to give you a precise answer here.

You can call a pharmacist and ask them to look it up.  (Only works if he/she is really nice, and is really bored or loves helping everyone.)

You can take it to your doctor at your next visit, and ask him/her to look it up. (Not likely to be real successful unless the doctor thinks it will affect your health or the health of someone in your immediate family.)

You can ask your neighbor, in the hopes that he/she has been taking that pill and accidentally recognizes it (BIG STRETCH!).

OR

You can look in a PDR (Physician's Desk Reference) which is a huge book printed every year that contains most medicines and information about them.  It has a section with pictures of pills made by each drug company, but it will be a chore to look it up any way you try.  Here is a link to PDR, and I think you can get a free trial version.  Hopefully, your pill will be one of the ones you stumble across.  The PDR is pretty much the definitive source for information on pharmaceutical products in the U.S.

LINK: http://www.pdr.net/pda-medical/

You may be able to find an actual copy of the PDR (fairly recent copy) at your public library.