Lithium Pharmacokinetics

[nibblerd]

Ever wonder what blood levels are like over 72 hours after dosing? I did. I found a PDF that was rather descriptive (here) and thought I'd share the main figures of interest with the community.

I guess that a lot of the patients have a high blood level to begin with, but I thought it interesting that most of them jump up to (or over, in the case of one poor guy) 1.5.

Seems quite obvious, but everyone's lithium level is near 0.00 at 72 hours.

Just an average of all the points on the last graph.

This is fun, too. Most people took 2 hours to reach the maximum blood level. The second section compares average figures for mentally healthy volunteers (single dose and steady state) and patients stabilized on lithium.

So right now I'm wondering how my doctor can say I can take all of my lithium at once at night time, without a morning "booster". Is anyone here on that sort of regimen without using the extended release form? I guess I just want to minimize the number of pills I have to take in the AM.

[SashaSue]

Well, how has your present dosing schedule working for you so far? That's what actually matters, not so much a bunch of charted randoms.

[nibblerd]

It sucks. I want to sleep in, but usually have to wake up at 8.30 to take my pills. I did it without food this morning and didn't really suffer until about an hour and a half later.. I also have this fantastic metallic taste in my mouth in the morning which doesn't go away until noon and after dosing at night. I'm more interested in switching to XR tablets than adjusting my IR dosing schedule, because the side effects after dosing are just.. I'd rather not have them. Less nausea with the XR, right?

[AnneMarie]

Yes, less nausea with ER.

[bpladybug]

I love my EX tabs. And I take them all in the evening.

[SashaSue]

It sucks. I want to sleep in, but usually have to wake up at 8.30 to take my pills. I did it without food this morning and didn't really suffer until about an hour and a half later.. I also have this fantastic metallic taste in my mouth in the morning which doesn't go away until noon and after dosing at night. I'm more interested in switching to XR tablets than adjusting my IR dosing schedule, because the side effects after dosing are just.. I'd rather not have them. Less nausea with the XR, right?

As everyone else has already said, the ER is less side effecty, and probably better all around for most people.

This is totally a side issue, but why do you have to get up at 8:30 to take lithium? I've always just taken whatever am meds whenever I woke up, and that's never seemed to be a problem.

[Aurochs]

So right now I'm wondering how my doctor can say I can take all of my lithium at once at night time, without a morning "booster". Is anyone here on that sort of regimen without using the extended release form?

Look at figure 2 again. See where the mean serum concentration is at 24 hours? It's not all that different from the concentration at 12 hours (the standard errors almost overlap). Consider what that means.

[AnneMarie]

My pdoc doesn't see it a big issue if I take the IR all at night. I don't feel any difference from the ER. Maybe if I was unstable it would be different. Truth be told, I like the IR because I only have to take one capsule instead of two tabs. And, it's a pink and white capsule, so it's pretty. How is that for priorities?

[nibblerd]

My pdoc doesn't see it a big issue if I take the IR all at night. I don't feel any difference from the ER. Maybe if I was unstable it would be different. Truth be told, I like the IR because I only have to take one capsule instead of two tabs. And, it's a pink and white capsule, so it's pretty. How is that for priorities?

I have to take FOUR capsules with IR, so two tablets would be a bloody improvement. I had to take three capsules inpatient, but it was horrible - a 600mg capsule (omg!), 300mg, and a tiny 150mg. I'd choose 3 x 300+1x150 over 600+300+150 ANY day of the week. That 600mg capsule.. *shudder*

Anyways, I'm going to push for a change to ER simply because I'm tired of the nausea, drooling, and other things that happen when I take IR at night.

[AnneMarie]

ER is better for nausea. I think I was on it for five years before I could deal with the IR.

I take that mongy 600mg capsule, btw. It competes with my big, blue, diamond 200mg Lamictal for space in my throat. Who thought diamond was a shape meant for the throat?