Dr. Phelps,
Let me first apologize if this question has been addressed somewhere in your archives and I missed it.

My child has been diagnosed with BP I disorder.  He has been mostly stable on a potion of lithium, abilify and lamictal, but the lithium (900 mg/day)is causing some unpleasant and potentially worrisome side effects.  He has all the signs of having developed kidney stones.  In the past we've wanted to take him off lithium but his doctor has cautioned against it.  Now, psych tells us that it is unlikely the lithium has anything to do with my son's apparent kidney problems, but a urologist would want to take him off of the drug first thing to find out so we should do so immediately.  An odd sort of construct.  I would think an urologist would have enough tricks up her sleeve to tell one way or the other whether lithium is the soure of the problem.

Until that time, I am wrestling with whether my son should continue to remain covered by the drug.  I certainly don't want to hurt his health, but I'm really afraid of his mood swings, which might be robust in a 13 year old.

Can lithium cause kidney problems? He doesn't drink nearly enough water. Do you think it's prudent to stop lithium before seeing urologist?  I saw what you said about Olanzapene as a quick stop gap.

I will be still now.

Thanks.
 

Dear Ms. B' --
How gracious of you to begin your note with that first line.  I see the conundrum: one doc firmly on one side of an action, the other rather firmly stating the opposite.  Where to turn for information? 

Never having encountered this particular issue before, nor seen reference in the literature (which doesn't carry a lot of weight, but does suggest that if there is indeed a relationship between stones and lithium, it's uncommon if not rare), let's do a search (I'll bet you've tried this already as well?).  Entering lithium renal calculi in Google led to an emergency room doc's summary of kidney stones which includes what appears to be a fairly thorough list of medications that can be culprits.  As you can see there, lithium is not on the list (it does appear on that page, which is why Google put it near the top of the list; but it's there in a discussion of interactions with possible treatments for kidney stones).  I didn't look through other basic primers on kidney stones, to see if lithium appears on anyone else's list of possible causes, which would probably be worth your time, just to make sure we're not missing some recognized problem. 

Entering the same search terms in PUB MED (the link shows you how, if you are not handy with that already), which list publications starting with the most recent, yielded no entries combining these search terms back to 1991! This strongly suggests the problem is not common, if it occurs at all. However, there is a 1985 article on parathyroid tumors.  Thinking I'd heard once that lithium might cause hyperparathyroidism rarely (you'll see the relationship in a moment, if it's not hitting you yet), let's search lithium parathyroid. Sure enough, there is a connection there.  

The connection: the parathyroid glands, which sit on top of the thyroid, regulate calcium in the bloodstream through "parathyroid hormone" (PTH). If they enlarge, they can make too much PTH, which leads through some very interesting physiology to increased blood calcium levels. However, that same physiology is also responsible for causing "low urinary calcium excretion", according to this abstract (this is leaving the realm of my recall; you might want to check this out with a nephrologist, the kidney doctors who are more like chemists, as opposed to the urologist, who is somewhat more like a surgeon in most cases, in terms of mind-set).  So this connection, although it sounds very suspicious, does not lead to stones, as far as I can tell.  

On the basis of these searches, I'd say that if there is a connection between your son's lithium and his stones, it is a very rare connection.  However, I am not an authority on this issue, and this was a very brief search of the literature, so this should not be considered a final word or anything like that.  Thank you for the prompt leading to this interesting tour. Good luck with your deliberations. 

Dr. Phelps
 

May, 2005