4 small RCT – 3 showing reduced headaches frequency over 1-4 weeks
Greater Occipital Nerve Block
SC every 12 weeks
10 – 25 mg
10 – 25 mg/day
150 mg ON
Safety alert *: In girls and women of childbearing potential, valproate should be initiated and supervised by a specialist and only prescribed when other medications have not been tolerated or have found to be ineffective. This is because of 30-40% risk of neurodevelopmental disability in unborn babies exposed to valproate (MHRA April 2017). Valproate should only be prescribed by following the MHRA guidance, including a signed contraceptive plan and signed consent form documenting discussion of the risks (see MHRA website).
(Tables taken from the British Association for the Study of Headache’s National Headache Management System for Adults 2019)