Q: Lithium & Kidney Stones|
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.
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
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 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.