TREATING MIGRAINE WITH DRUGS: METHYSERGIDE (DESERIL) AND CLONIDINE

Posted: December 20th, 2010 | Author: admin | Filed under: Pain Relief-Muscle Relaxers | No Comments »

Methysergide (Deseril)
Another very potent inhibitor of 5HT is methysergide, which is an effective anti-migraine prophylactic. Prolonged use may lead to fibrous thickening of certain structures such as the kidneys, so that this therapy should not be prolonged for more than three months at a time, an interval of one month being required before another course can be started.

Clonidine
This drug was first used in the treatment of high blood pressure and it acts both on the brain and on blood vessels. Centers in the brain which control blood pressure are affected in such a way that they cause blood vessels to dilate, while the blood vessels themselves are made less responsive to noradrenalin; both of these effects serve to reduce blood pressure.
In smaller doses, clonidine should prevent many of the chemical changes which spark off a migraine attack; Dixarit, its proprietary name, contains about a quarter of the dose of clonidine used for high blood pressure. When, in this dosage, it prevents migraine, it works well, but people who do not benefit from initial treatment will not benefit with increasing dosage.
Although several trials have found that clonidine confers no benefit when compared to a placebo, some physicians find it useful in certain circumstances, as the almost total lack of side-effects often make it a drug of first choice in prophylaxis, especially in women whose migraine attacks occur at the time of the menstrual periods. Like other preventive drugs, it may take up to two weeks for the effects to become manifest.
A group of medical students were given Dixarit or a placebo prior to a party in which the intake of wine and cheese was excessive. The next morning the Dixarit-treated group developed headache significantly less often than the placebo treated group. This result, although not scientifically reported, is interesting because cheese and red wine are most potent in producing headaches. Tyramine is only one of these factors present in red wine. The ‘hangover’ headache is due to a variety of factors, one of which is that the alcohol dehydrates the brain tissue to give low pressure headache. Some of the chemicals in alcoholic drinks have effects on their own, acting to cause a vascular headache of the migraine type. The part that an excess of tobacco plays in the hangover headache is uncertain but nicotine is a well-known precipitant of headache.
The main compounds to influence platelet activation are called thromboxanes. These are derived from one of the fatty substances which may trigger a migraine attack. These free fatty acids are converted into substances (pro-aggregating agents) which eventually cause the platelets to clump together. These also cause constriction of vessel walls, which react by producing substances with opposite actions (i.e. they convert the free fatty acids into inhibitors of platelet aggregation and into powerful dilators of vessel walls).
Altering these compounds in the body should in theory have a marked effect on migraine, especially if platelet activation could be prevented without changing the size of blood vessels. Constriction of the vessel wall is the first part of the migraine cycle and breaking this pattern would be therapeutically helpful. Most substances which inhibit the production of thromboxanes in the platelets also inhibit the production of anti-aggregating substances in the vessel walls as both have similar initial production stages. Preventing dilatation – the cause of the pain – will produce relief by the same mechanism as the many vasoconstrictor medicines which are effective during an acute attack of migraine.

*65/152/5*

Share and Enjoy: