Is resorting to a doctor considered a solution if a worshiper has been experiencing intrusive thoughts (waswasah) during the Isha’ prayer for a long period, reaching two years for a single prayer, and if these thoughts subside for a week when ignored, only to return?

The cure for obsessive thoughts is to turn away from them and not pay attention to them. You must continue to repel them until Allah removes them from you. Treatment is a legitimate matter, and modern medicine has discovered treatments and medications that reduce obsessive thoughts and help in getting rid of them. Therefore, we advise consulting a trusted doctor.