Blood level testing?

[mbcracken]

I'm new here and have threw quick intro of myself in the Foyer earlier today.

I am currently on phenytoin which are 100mg capsules. My dosage is 450mg per day so I alternate 400mg then 500mg every other day. After my breakthrough on Monday, the ER blood tests came back at 7.8. Obviously, this is below the 10-20 therapeutic range but my neurologist has always to tried to keep me at ~10 over the last 12 years. I've only had to bump up once from 300mg/daily to 450mg/daily. This gives me the impression that it was not that far out of range. Do you think that is a fair statement or assumption to take? I understnad if this question results in ..."Well, it depends".

Also, how often do those on phenytoin or dylantin get blood levels checked? My neurologist has not tested me for over 2.5 years and informed me that frequent blood draws could result in inaccurate level counts. That seems really long for me to not be tested. Any thoughts or recommendations on how frequent one should be tested?

Cheers,
Mike

[Nakamova]

When I was on Dilantin, my neurologist tested my blood once a year, both to check liver function (which can be affected by Dilantin), and also to check blood serum level. My levels were usually quite low, somewhere around 5, but I tend to require less for seizure control, and my dose was only 100mg per day. The levels can vary depending on the time of day, and on your metabolism. Since there are so many unknowns, one of the few things the neurologist has to go on is whether the med is working or not. If you have a breakthrough, the easiest explanation is that your levels are too low. That doesn't mean that it's the only explanation. And if you feel uncomfortable bumping up your dose, let your doc know. (If I were "compliant" with everything my neurologist asked me to do, I'd be on twice the dose that I'm on now.)

[Endless]

I'm really new to all this. So I know next to nothing.

My first blood level check was in the hosptial when I checked in for a video eeg, a couple of months after starting keppra. I understand that's a standard test when in-patient, otherwise it probably wouldn't have been done unless there were problems. It's the only one done to date.

I wonder if low drug levels in your blood could have anything do do with either liver function or with other medication you may be taking, or with alcohol consumption (if you drink at all)?

[Nakamova]

Alcohol can affect Dilantin absorption. If I remember right, they reinforce each other -- so both the alcohol and the med get absorbed faster, and you can feel "sedated" more quickly than you would otherwise. So alcohol can make the levels less consistent, one reason why it's considered a no-no. Plus the dehydration and electrolyte imbalance that can happen after drinking can trigger seizures for some people.

[skillefer]

Don't forget that calcium can effect dilantin absorption. So, if you take a calcium supplement around the same time you take the dilantin, the calcium will inhibit the absorption. also, the dilantin can inhibit vit D absorption. Deficiency in vit D can inhibit calcium absorption...I know...it's a vicious cycle.

[Crystal11]

While on Tegretol XR, I have to get tested every three months- in order to get my refill. With my Keppra XR, if I get tested it would take a few days to get the results back- so they don't usually test levels. With my Lamictal, I have not been tested before taking it and they don't require me to have testing for it.
Tegretol XR needs to be checked to make sure liver and other organs aren't getting toxic levels, or to make sure you're getting the right amount of meds in your system.
Mine is usually at 8-10 every time I'm tested.
I will be getting off of Tegretol XR hopefully soon! yay

Take care,
Crystal

[carlos.fonke]

Mike, I would think annual tests are the minimum. I've been on phenytoin before and have never gone more than 10 months. In fact, that's the longest I've gone for any epilepsy medication.

[Zoofemme]

Dilantin I had been scheduled for testing once a week as they increased my levels...I never made it to the second week though since it sent me into status but at the ER my levels tested low.

Tegretol I was tested every two months...my levels were always low, even at 2400 mg.

Trileptal and Lamictal I've only had levels tested twice, two years ago and last month...levels were low both times.

Just had Topamax levels done, haven't heard back yet what those were.

*edited cause it is too ealy in the morning and I'm not sure what I'm doing yet*