Botulinum Toxin A in Frequent and Chronic Tension-type Headache

Chronic tension-type headache (CTTH) is an underestimated disabling condition that affects a large number of patients. The treatment options for both episodic tension-type headaches, but especially CTTH are few. Poor long-term effects of existing treatment for CTTH (Sarotex, SSRIs, physiotherapy) are reported. Patients with CTTH also have a high risk of developing drug overdose headache (MOH). Non-drug treatments with physiotherapy or alternative medicine also show poor long-term effects. Literature reviews show that there is surprisingly little research on CTTH. Some small clinical trials report a good effect of treatment with botulinum toxin A, but larger controlled trials are needed to confirm or deny this. The investigators will study effect of treatment with botulinum toxin A in CTTH in BACT study, and will include participants with both frequent and chronic TTH with 10 or more headache days per month. If BACT outcomes are positive, this will open a possibility for a new treatment for TTH patients.