What is a round yellow pill with "dan 5619" and a "5" on the other side? And a grey round pill with op on one side and 15 on the other side ?

Not Medical Advice: Round yellow pill with imprint DAN 5619 on one side and 5 on the other side is Diazepam 5 mg. It is used in the treatment of anxiety.

Monday, February 06 2012
Source: http://www.drugs.com/imprints/dan-5619-5-255.html