Proscar and dizziness
Avoid driving and doing other tasks or actions that call for you to be alert until you see how this medicine (finasteride 5 mg tablets) affects you. To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs. This medicine may affect certain lab tests. Rare side effects include headache, rhinitis (stuffy nose) and back pain.