I found a small grayish pill in my sons room with a k 57 on it, what is it?

Pill imprint K 57 has been identified as Oxycodone hydrochloride 20 mg.

Oxycodone is used to help relieve chronic pain (such as due to cancer). It belongs to the drug class narcotic (opiate) analgesics. It works in the brain to change how your body feels and responds to pain. This drug is only available upon prescription of a doctor.

There is no proven risk in humans during pregnancy but consult a doctor about the possible risks of harming your unborn child.

This drug may make you dizzy or drowsy so avoid driving, or any activity that requires alertness. Remember to swallow the tablet whole. Chewing or crushing the tablet may lead to rapid release and absorption of oxycodone and can cause a potential fatal overdose.

Listed below are side effects that can occur when taking this drug:

Learn Tips to Manage Your Chronic Pain from WebMD.

Thursday, December 31 2015
Source: http://www.drugs.com/imprints/k-57-15464.html