Even though most people who suffer from sinusitis need not see their GP as the condition is generally caused by a viral infection only; in some severe cases if the condition doesn t pass within two to three weeks it means the patient has acute sinusitis. Also known as chronic sinusitis Dr. Bulbul Gupta ENT Specialist at Lybrate says that when the sinusitis becomes difficult to treat it may take several months before one feels better. Here are some of the most effective treatment the doctor suggests: Treating sinusitis with over-the-counter painkillers - Over-the-counter painkillers help inreducing inflammation to some