General Notes

Choice of prophylactic treatment should be based on individual patient factors such as presence of co-morbidities, potential for drug interactions and possibility of pregnancy.

Effectiveness of prophylactic medication can be reduced by overusing analgesics or triptans for treatment of acute migraine.

Where there are concerns regarding medication overuse, the risk of medication-overuse headache and the potential reduction in efficacy of prophylactic treatments should be discussed with the patient.

Following dose optimisation, it is recommended that each trial of a prophylactic treatment is continued for 3 months before assessing efficacy.

Good response is a 50% reduction in severity and frequency of attacks.

Treatment failure is a lack of response to the highest tolerated dose used for 3 months.

Migraine prophylaxis should be reviewed every 6 to 12 months and consideration given to a trial reduction.

Following specialist advice, candesartan and sodium valproate may be considered for migraine prophylaxis. Neither drug is licensed for this indication, however such use is referenced in national guidelines.

Sodium valproate is associated with a significant risk of birth defects and developmental disorders in children exposed to valproate in utero.

For women of childbearing potential sodium valproate should only be considered as a prophylactic treatment when:

  • other treatment options have been exhausted
  • conditions of the Pregnancy Prevention Programme are met.

MHRA VALPROATE AND DEVELOPMENTAL DISORDERS ALERT

IMPORTANT NEW RESTRICTIONS MHRA (JANUARY 2024): Additional safety measures include changes to initiation of Valproate and ongoing prescription review for MALES and FEMALES.
Valproate must not be prescribed to women/girls of childbearing potential unless enrolled in pregnancy prevention programme (PPP).

Source: MHRA Drug Safety Update Jan 2024: New safety and educational materials to support regulatory measures in men and women under 55 years of age.

MHRA Resources: MHRA information page, Patient Guide, Patient card, Patient Information Leaflet, Healthcare Professional Guide, Annual Risk Acknowledgement Form for female patients and Risk Acknowledgement Form for male patients starting valproate

Pharmacological Prevention of Migraine

Preferred list (P)

PROPRANOLOL

Total list (T)

TOPIRAMATE

  • Restriction: For use in patients who have not responded to prophylactic treatment with at least one other agent [SMC advice].
  • Contraindicated in pregnancy and in women of childbearing potential if not using a highly effective method of contraception.
  • Topiramate can impair the effectiveness of some hormonal contraceptives. See FSRH Clinical Guidance: Drug Interactions with Hormonal Contraception for suitable contraception methods.

AMITRIPTYLINE

PIZOTIFEN

FROVATRIPTAN

  • For menstrual migraine prophylaxis (off-label use).

Botulinum Toxin A

Specialist use only (S2)

BOTULINUM TOXIN TYPE A powder for solution for injection vials (Botox®)

  • SMC restriction: For use in adults with chronic migraine whose condition has failed to respond to ≥3 prior oral prophylactic treatments, where medication overuse has been appropriately managed. [SMC Advice February 2017].

Human Monoclonal Antibody

Specialist use only (S2)

ERENUMAB solution for injection pre-filled pen (Aimovig®)

  • SMC restriction: For the prophylaxis of migraine in adults who have at least four migraine days per month and in whom at least three prior prophylactic treatments have failed [SMC Advice April 2019]

FREMANEZUMAB solution for injection pre-filled pen(Ajovy®)

  • SMC restriction: For the treatment of patients with chronic and episodic migraine who have had prior failure on three or more migraine preventive treatments. [SMC Advice January 2020]

NHSL Joint Adult Formulary Key

To indicate the category of a formulary medicine, updated sections adopt the following key:

Preferred list (P): First-line formulary choices.

Total list (T): Alternative choices when preferred list options not effective/not tolerated, or not indicated.

Specialist initiation (S1): Specialist initiation, or on the advice of a Consultant or Specialist Practitioner in this therapeutic area. Continuation in primary care is acceptable.

Specialist use only (S2): Supply via hospital, Homecare Service or a hospital based prescription (HBP) for dispensing by community pharmacy. Not prescribed in primary care setting.

Editorial Information

Last reviewed: 31/01/2022

Author(s): NHSL.

Version: Please refer to the introduction section for an explanation of the review dates above.

Approved By: ADTC

Reviewer name(s): ADTC.