Posted by DocGreg on March 12, 1999 at 15:49:03:
In Reply to: Imitrex dosage frequency posted by pinksharkmark on March 11, 1999 at 15:18:26:
Actually, the official recommendation is not to exceed 2-3 doses per week (if you can believe that!)
This is mainly because they have not studied the safety of the medication when treating more than 4 headaches per month (studied done on people with migraines, not clusters).
This is not to say that more frequent use is unsafe...just not yet studied, so we can't say for certain.
I have used Imitrex multiple times per day for months...as many on this board have...so in my limited study, it is safe to use more than 2 times per week.
How many times per day? Well, the half life of imitrex is 2 hours (time it takes for the body to elimiate half of the drug). I would not take second full strength doses of Imitrex closer than 2 hours together...ever. 4-8 hours would probably be safer. If you are not taking the full strength (100mg oral, 25 nasal, 6 inj) then you might be safer to take it closer together...but I really wouldn't violate the 2 hour rule of thumb.
Now I know that they have studied people taking 2 doses in a 24 hour period...without major problems, but I don't think they've looked much at 3 or more. The risk is mostly vasospasm (constriction of the arteries, possibly causing a heart attack). So be careful.
I can't tell you that it is safe to take as much as you (and frankly, sometimes me) are taking the medication. All I can say is that it might be. I know when my head is exploding, I'm often willing to take the risk. But that's something you need to decide for yourself.
Sorry I can't give you a definite answer.
Good luck
Greg