From Mr C. R. Cleverly, MRPharmS
SIR,—I was interested to read in Part 3 of the article on the menopause (PJ, November 27, p862) that oestrogens have both calcium channel blocking and monoamine oxidase inhibitory activity.
It is tempting to speculate as to whether these actions may offer an explanation for the preponderance of migraine in women of child-bearing age, particularly as the incidence drops after the menopause.
Many of the recognised food triggers for migraine are high in tyramine and appear in the list of foods contraindicated in MAOI treatment in depression, and the calcium channel blocker dilatory action on arteries supplying the brain may well contribute to the effect.
Perhaps the cyclical variation in the incidence of migraine in women may be, indeed, hormonal in origin, but mediated through these actions.
Are there any data relating to the incidence of migraine in women with a history of migraine now receiving tamoxifen which might support this hypothesis? It is probably too soon for such data on raloxifene, but it could be of use in migraineurs (migraineuses?) who continue to react to oestrogen in HRT if this relationship can be established.
Roger Cleverly Sherborne, Dorset