lithium levels

once ingested, regular release preparations produce peak serum lithium levels in 1-3 hours, compared with 4-12 hours after ingestion of sustained release preparations (such as lithobidr). lithium initially occupies a volume of distribution of 0.4 liters per kg of body weight (approximately equivalent to the vascular space). then, over the next 6-8 hours, the drug gradually moves intracellularly and achieves a final volume of distribution of 0.6-0.9 l/kg (equivalent to the total body water). the highest levels are found in the brain and the kidney where lithium exerts most of its toxic effects.lithium is excreted almost entirely by the kidney. however, anywhere from 60-75% of the filtered load is reabsorbed in the proximal tubule. since lithium is handled by the kidney in a manner very similar to sodium, any underlying condition with volume or sodium depletion will result in increased lithium reabsorption. for example, patients with vomiting, diarrhea, dehydration, congestive heart failure, excessive exercise, or even a low sodium diet are at risk for lithium toxicity via increased reabsorption of the cation at the level of the proximal tubule.

lithium toxicity typically occurs in one of three scenarios: acute overdose in a patient who does not normally take the drug, acute overdose in a patient chronically taking lithium (acute-on-chronic), or chronic toxicity resulting from accumulation of the drug during therapeutic use. acute and acute-on-chronic lithium exposures occur as the result of accidental or suicidal ingestion of excessive amounts of lithium. generally, toxicity resulting from chronic accumulation of lithium is more severe. in addition to sodium depletion, other factors that can contribute to chronic toxicity include concomitant drug therapy with drugs that decrease glomerular filtration rate (gfr) such as angiotensin converting enzyme (ace) inhibitors or nonsteroidal anti inflammatory agents, and the development of nephrogenic diabetes insipidus. lithium is the most common cause of drug induced nephrogenic diabetes insipidus which is characterized by polyuria, polydipsia, hypernatremia, and low urine osmolality. this condition causes volume depletion, which in turn results in increased lithium reabsorption and subsequent toxicity.

hope this helps

ps:what's dd?

dd stands for darling/dear daughter.

thank you for all that information but do not think any of this applies to my dtr. she constantly drinks; isn't using anything that would increase lithium levels....and i still don't understand why her lithium level did not increase at all after a 300 mg. increase. when she had the 450 mg increase, it zoomed to toxic levels.

i think it has to be the zyprexa and it has finally metabolized and distributed to all cells involved, thus the stuporous effect. i'm at a complete loss.

thanks again. i do appreciate it.

leslie

Leslie, a couple things to be mindful of here:

1) What is list of ALL her current meds?...just lithium and zyprexa?

2) When a person who is no longer manic and is on both lithium and an antipsychotic (used to address the acute mania), the person can often present as being overdosed on the antipsychotic...necessitating a reduction in the antipsychotic (no longer manic). The same rule applies for Benzos.

3) I assume she has had a drug tox screen for drugs of abuse (street drugs that could have been smuggled in...I used to work detox, my heroin addicts hated me because I often took away a stash being smuggled in. So in saying this, what are the chances that her urine is dirty for a smuggled in street drug?).

3) Also, time released lithium runs a chance of generating a 10% higher 12hr serum levels than same dose of standard lithium. Which brings also to mind, the need to ensure that the blood draw is not less than the 12 hr window...or longer.

4) Hmmm, just another interesting note...how has her symptom/side effect profile at 1.32 compare to this most recent episode at 0.6? Shouldn't she had had more of side effects with the 1.32? If she is presenting more on the current 0.6 with being stuporous tends to make me wonder that something other than the lithium is going on. Concurrent drug abuse, a recent unwitnessed seizure or seizure activity (history of seizure disorder?), interaction of meds...something....just lithium as the culprit isn't jiving.

5) When she gets her next lithium level, it may be interesting to see what her other labs show too....TSH, T4, chem panel.

6) Any Neuro consults of recent?...to rule out underlying neurological conditions.

Just my thoughts in a nutshell.

Wolfie

Leslie, a couple things to be mindful of here:

1) What is list of ALL her current meds?...just lithium and zyprexa?

2) When a person who is no longer manic and is on both lithium and an antipsychotic (used to address the acute mania), the person can often present as being overdosed on the antipsychotic...necessitating a reduction in the antipsychotic (no longer manic). The same rule applies for Benzos.

3) I assume she has had a drug tox screen for drugs of abuse (street drugs that could have been smuggled in...I used to work detox, my heroin addicts hated me because I often took away a stash being smuggled in. So in saying this, what are the chances that her urine is dirty for a smuggled in street drug?).

3) Also, time released lithium runs a chance of generating a 10% higher 12hr serum levels than same dose of standard lithium. Which brings also to mind, the need to ensure that the blood draw is not less than the 12 hr window...or longer.

4) Hmmm, just another interesting note...how has her symptom/side effect profile at 1.32 compare to this most recent episode at 0.6? Shouldn't she had had more of side effects with the 1.32? If she is presenting more on the current 0.6 with being stuporous tends to make me wonder that something other than the lithium is going on. Concurrent drug abuse, a recent unwitnessed seizure or seizure activity (history of seizure disorder?), interaction of meds...something....just lithium as the culprit isn't jiving.

5) When she gets her next lithium level, it may be interesting to see what her other labs show too....TSH, T4, chem panel.

6) Any Neuro consults of recent?...to rule out underlying neurological conditions.

Just my thoughts in a nutshell.

Wolfie

hi wolfie,

when her levels were 1.32, her speech was thickened, was highly tremulous and c/o nausea.

yes, she's only on the lithium and zyprexa. i still don't understand why her levels didn't increase w/the 300 mg increase.

anyway, i didn't see her when she was stuporous-just taking reports.

this program does not allow any visitors, only parents, so it's highly doubtful anything was smuggled in. but then again, my dtr was telling me that she was huffing dusting spray as a cheap high.

today when i saw her, she was hypomanic.

granted, there were many people there donating new bedspreads/curtains and lamps for ea of the girls' rooms. but hrs later, i could see her crashing.

she did take her meds last noc yet she was up all noc long. this depakote is totally unpredictable- or is it the bipolar? she continues to rapidly cycle but maintains that she feels more stable. i don't see it.

i also don't think it's the lithium.

i also know she's not taking anything that would interact w/lithium.

i have to wonder if she really took her zyprexa last noc-she didn't the noc before, when she found out it makes you gain weight.

i was going to suggest to her new psychiatrist on wednesday, that they decrease the zyprexa from 15 to 10 mg.....but after what i saw today, i'm more concerned than ever.

and whenever they draw her lithium levels, they also check her tsh & t4; not sure about the chem panel. she's also on reg lithium carbonate, not the er. she's been on so many different meds, i'm really starting to lose hope, esp after today.

thanks for your input- it's always helpful.

leslie

this depakote is totally unpredictable-

??????

Couple things:

1) Tox screen?...folks who want to use, especially when hypomanic/manic, can be very creative in getting a buzz....depending on the substance, can make you elevated or crash either way...monitor times of opportunity and behavior after. Another source, could a patient on the unit pass her a med that was meant for that patient (but was not taken)? How good are the staff at checking for contraband entering the floor...body checks, belonging checks, anything that comes on the floor?

2) Is she cheeking her Zyprexa at HS (even her Lithium)? Good mouth checks? Zydis? Weight gain, yeah...but so does Lithium.

3) Depakote: The psychiatrist I worked with started very manic folks off with daily mg dosage (24hr) as 10 times the body weight, divided dosages. Maintenance reduced down to 7 times the body weight. Worked well. Does this correlate with daughter, past or current?

4) Has she been on both Lithium and Depakote together?...one strategy for rapid cyclers. Dosage of anticonvulsant titrated to response/body weight. Tegretol can be used, but increases the risk of neurotoxicity...needs monitored.

5)With rapid cyclers, some have benefited from Rx of T4 to reach a goal of high-normal to slightly elevated hyperthyroid levels.

Just some other thoughts in a nutshell.

Try not to lose hope. I know it has been rough for you. Bipolar at this age is not pretty, especially with rapid cycling...whatever the cause.

HUGS

wolfie,

have you heard using seroquel for bipolar?

tiff received it prn (100mg) at the hospital with initially, good effect....she was extremely sedated.

then the seroquel made her less sedated, so they changed the prn to thorazine 50 mg.

i was just thinking if they took her off the depakote, and started her on seroquel 300-400 mg qhs.....i don't know, forget it.

i've read about depakote and tegretol.

tegretol especially has significant interactions w/lithium, as well as many other meds. but i know it's used for rapid cycling as well as aggression (which tiff is prone to) and controlling impulses.

i'm just thinking aloud....thanks for listening.

leslie

Let me know if you need anything else, Leslie.

Glad to listen.

my dd has been on lithium 450 mg po bid for a long time.

her lithium levels have consistently been 0.6-0.7.

a few months ago, her outpatient psychiatrist increased her lithium by another 450 mg, totalling 1350mg qd.

2 weeks later, we drew a level and it sky-rocketed to 1.32 so she was put back on the 900 mg.

in her most recent hospitalization on admission, her lithium level was 0.6.

he increased her lithium 300 mg, totalling 1200 mg qd.

on her day of discharge, he had another level drawn and i never heard anything.

this substance abuse program she's currently residing at, reported to us that she is stuporous with thickened, slurred speech.

so i called the hospital to find out her lithium level at discharge- it stayed at 0.6.

it had been more than 2 weeks since her increase, so why didn't it go up?

and she was started on zyprexa 15 mg a few wks ago also but she was fine last weekend when we saw her. the staff just said she was a little slow in the morning-now they're reporting a significant deterioration.

can anyone help me understand her lithium levels not changing?

my first thought re: the stupor and slurring was lithium toxicity.

can it take sev'l weeks for lithium or zyprexa to take its' total effect?

what would cause this and why?

the staff arranged a consult w/a reputable psychiatrist for this coming wednesday. but even when we saw her today, she was a completely different person.....non-communicative and trance-like. and she also refused her meds last noc- not good for someone w/bipolar.

anyone, please?

leslie

Could it be that she has been cheeking some of her meds out of fear of her previous toxic reaction? Pehaps cheeking has caused her to convert into a hypomanic state (so to speak) and she is not sleeping or her quality of sleep is very poor? In spite of her stuporous appearance is she seemingly restless? What about her urine tox? Is she clean cause that could be the issue. I'm just throwing some thoughts out there, but it is odd that she would be taking an increased dose of Li and not show an increase in serum levels if of course her fluid/salt intake hasn't changed.

??????

Couple things:

1) Tox screen?...folks who want to use, especially when hypomanic/manic, can be very creative in getting a buzz....depending on the substance, can make you elevated or crash either way...monitor times of opportunity and behavior after. Another source, could a patient on the unit pass her a med that was meant for that patient (but was not taken)? How good are the staff at checking for contraband entering the floor...body checks, belonging checks, anything that comes on the floor?

2) Is she cheeking her Zyprexa at HS (even her Lithium)? Good mouth checks? Zydis? Weight gain, yeah...but so does Lithium.

oops...I guess I should have read all the posts before adding my thoughts