My leg cramps up and hurts to walk, more often now. Are there any meds that cause that as a side effect?

No. Walking, especially uphill and experiencing cramping/tightness in muscles of the calf or buttock area is called claudication, and when stopping for 5-10 min the symptom goes away. Walking again for will trigger cramping, and this is indicative of pad (peripheral arterial disease), poor circulation, and you should see your doctor.
Probably not meds. Dr. Isobe is right. The first thing you want to make sure is that this is not arterial claudication. Medications that help to control cholesterol (statins) can cause leg pain, however that kind of pain is not usually related to exertion. One other thing to remember is that varicose veins can also cause claudication. Bottom line, if you are getting exertional leg pain, better see your doctor.