Rubarb
My husband has had a similar thing for years. We have them almost stopped. He takes vitamin B12 everyday and Black Cohosh in capsules (herb)with plenty of water. We also discovered that if he takes an Actafed or an antihistimine with the ingredient tripolatine (tripoladine?), at the onset of the head ache, he can lessen them or head it off off. Watch out for hidden alcohol. He can't eat anything that has alcohol in it, even if it has been "cooked" out of it as in sauces made with wine etc. He can stant corn syrup, honey and fructose (fruit sugar) but no other kinds.