What is a white round pill with M724 on it?

Not Medical Advice: A white round pill with the imprint M 724 has been identified as Tizanidine hydrochloride 4 mg and is sold under the brand name Zanaflex. It is used in the treatment of cluster headaches and muscle spasms, and is part of the drug class skeletal muscle relaxants. Common side effects include dry mouth, tiredness, flushing, dizziness, constipation, drowsiness, and weakness.

Thursday, February 02 2012
Source: http://www.drugs.com/imprints/m-724-10288.html