There's general agreement that nonsteroidal anti-inflammatory drugs (NSAIDs) can help ease pain and swelling caused by a muscle strain. However, some research studies have shown that using NSAIDs for a long time after a muscle strain gets in the way of healing. Since it's been three months and you still have pain, talk with your doctor. You might need to see a physical therapist to regain muscle flexibility and strength and to learn other ways of dealing with your pain besides medication.