Symptoms returning after 18 months

Hello. After having a steroid injection in my left wrist in April 2012, I have been symptom-free until 3 weeks ago. The tingling, and jabbing pains, although spasmodic, are gradually returning in both hands, left worse than right (I'm a southpaw). I am keen to prevent this getting any worse. I have made some minor changes with my driving position (commuting 1 - 2 hours daily); and at work with my desk and chair which has helped. Unfortunately I have lost my wrist splint (L). Would it be ok to ask my GP for splints for both wrist for use at night and when resting, or could you recommend something else to help relieve the symptoms?