I was prescribed oxaprozin. Would it have neg. Side effects?

Potential. Uncommon. All meds have potential side effects, & this is no different. Potential side effects of this type of med include GI upset, ulcers/gastritis, kidney probs, elevated blood pressure, fluid retention, rash, abnormal liver tests, ringing in your ears, & more. If this sounds long, don't be surprised, most meds have similarly long lists of potential but uncommon side effects. Do risk-benefit analysis.
Daypro – oxaprozin. side effects can include: abdominal pain, indigestion, bloating,belching, ^'ed gas, constipation, loose stools, nausea, vomiting, ringing in ears, hearing loss, insomnia, sedation, rash, v appetite, weight loss, Vomiting coffee ground -like material, black & tarry or bloody stool, frequent,painful or difficult urination, decreased urine, weakness, fatigue, ^ bleeding/ bruising, headache.