Does oxycodone cause edema?

I have a feeling that my father is back to taking oxycodone. He finished a rehab program several months ago but He looks really bad recently. His face stays red as a tomato, he has severe edema (his feet can't even fit into his shoes), constant sweating, and extreme sleepiness. I asked him if he was back on the pills and of coarse he denied it. I'm just wondering if these symptoms sound anything like what the oxycodone will do to you.

Oxycodone is a Category 2 Schedule drug with a high risk of abuse. The Symptoms of abuse are what you described. I checked my Mosbys and Tabers Medical Books, and both say the same. I hate to give advice on here unless I see it in bold print.
The only thing higher is a class 1, and thats cocaine...Do you know who is prescribing it?

Edema can be a reaction, and if he has edema, that can cause grave dangers, of which I am sure you are aware of.
Edema is the increase of interstitial fluid in any organ. Generally, the amount of interstitial fluid is in the balance of homeostasis. Increased secretion of fluid into the interstitium or impaired removal of this fluid may cause edema.

Generation of interstitial fluid is regulated by Starling equation of Tissue Fluid which states that it depends on the balance of osmotic pressure and of hydrostatic pressure across the capillary walls. Consequently, anything that increases oncotic pressure outside blood vessels (for example inflammation), or reduces oncotic pressure in the blood (states of low plasma osmolality, for example cirrhosis) will cause edema. Increased hydrostatic pressure inside the blood vessel (for example in heart failure) will have the same effect.

Abnormal removal of interstitial fluid is caused by obstruction of the lymphatic system, for example due to pressure from a cancer or enlarged lymph nodes, destruction of lymph vessels by radiotherapy, or infiltration of the lymphatics by infection such as elephantiasis.

It could be the oxycodone causing the fluid retention. It also could be kidney failure or heart disease. Persons with CHF frequently retain fluid around their ankles as well as under their eyes. If he truly is off of the oxycodone, then there is something else causing this problem. Get him to his doctor as soon as possible.