While many supplements have some evidence for benefit in treating migraine  (such as magnesium  and vitamin B2), knowing exactly which supplements to select and how to use them safely can be overwhelming given the hundreds of formulations available. The following are a few key tips intended to make choosing the right supplement a little easier:
Choose supplements that have been assigned an 8-digit Natural Product Number or “NPN”.
An NPN indicates that a particular product has met Health Canada approval for manufacturing standards, product quality and safety. An NPN provides assurance that the product contains only the stated ingredients and is free of contaminants or other hidden ingredients. Caution must be exercised if purchasing supplements that are manufactured outside of Canada (for example online) as other countries may not have the same rigorous supplement regulation process, increasing risk of exposure to an unsafe product. NPNs are printed clearly on product labels:
No specific supplement brands have demonstrated superiority over others.
A generic brand (or store brand) should work just as well as a name-brand supplement. The key is to select a product that contains the active ingredient in the strength that has been recommended to you.
Unfortunately, some supplements are not readily manufactured in strengths commonly recommended for migraine. For example, vitamin B2 (riboflavin) is typically only found in 100 mg tablets. As the recommended dose for migraine prevention is 400 mg once daily, 4 tablets must be taken together to achieve the intended dose. If you are not able to find a formulation or strength, it’s always worth checking with your pharmacist as sometimes they can order in certain products or strengths that are not routinely stocked on their store shelves. Alternately, pharmacies that offer specialized compounding services may be able to work with you to prepare a custom supplement formulation.
Check with your pharmacist before starting any new supplement to make sure it is safe to combine with any other medications or supplements you are already taking.
Just because a product is natural does not guarantee it is safe or effective. Pharmacists have expertise in drug interactions and access to reputable drug information resources that may not be readily available to doctors or the general public.
If you are looking to learn more about a particular supplement the following resources are free, reputable and easy to use:
- “About Herbs” – Reports brief information on potential uses, side effects  and drug interactions of hundreds of natural health products. Available here: https://www.mskcc.org/cancer-care/diagnosis-treatment/symptom-management/integrative-medicine/herbs/search 
- “Medline Plus Herbs and Supplements” – Reports more detailed information on potential uses, side effects, drug interactions and potential effectiveness of hundreds of natural health products. Available here: https://medlineplus.gov/druginformation.html 
About Natural Health Product Regulation in Canada. Health Canada. Accessed online Jun 23, 2019 <https://www.canada.ca/en/health-canada/services/drugs-health-products/natural-non-prescription/regulation.html >.