Posted by ed_uk on March 21, 2005, at 13:43:49
In reply to Re: Tegretol, Dilantin..... » ed_uk, posted by Ritch on March 21, 2005, at 10:53:03
Hi Mitch!
>Yes, there is a new one called Equitrol.
We've got three different controlled release carbamazepine brands here, we don't have Equitrol though, it sounds good. Do you think you'll try it soon?
>I'm wondering since I'm so med sensitive, that I could get by with just 100mg/day
Most people need 200-500mg phenytoin for epilepsy, the plasma concentration of phenytoin is *not* proportional to dose. At doses <200mg, the plasma conc is often very low indeed. It's difficult to to say though because you're on Depakote. Depakote often raises the plasma conc of phenytoin- but may lower it in some people!! Also, phenytoin often lowers the plasma conc of Depakote. During the period of dose titration of phenytoin, measuring the plasma conc is important because small dosage increases (eg 25mg) can produce large increases in plasma conc, this is because the relationship betweeen dose and plasma conc is non-linear. Phenytoin's also got quite a narrow therapeutic index, toxicity may occur if the plasma conc is too high. With phenytoin, it's often best to avoid generics and to always use the same brand name, different brands may have slightly different bioavailabilities, this can sometimes be enough to produce a clinically significant change in the plasma concentration.
Best regards,
Ed.
poster:ed_uk
thread:471753
URL: http://www.dr-bob.org/babble/20050317/msgs/473633.html