Q:  Peripheral Neuropathy & Lithium

Thank you for your wonderful site, Dr. Phelps.

I am on 900mg lithium, 0.112 Synthroid, 1.0 Rivotril (and I struggled and succeeded getting off Xanax, but had great difficulty with Rivotril.  These drugs have been taken for about 20 years.

In the past few years, I developed peripheral neuropathy (like carpal tunnel) and after a cerebral stroke-like event upon withdrawal, I get headaches. 

My question:

Is peripheral neuropathy due to high lithium levels; I also have very salty membranes, and drink tons of water at night;  I worry that my lithium level is too high for me.  (last count 1.2 after 2 hrs. of ingestion). 

I see my doctor in 2 weeks to see how I stabilize on an increase in Rivotril dose - a dismal failure at withdrawal after trying a year.

Thank you.
Squiggles
 

Dear Ms. or Mr. Squiggles -- 
On a quick literature review using Pub Med (try it; "lithium neuropathy" was the search term I used) there appears to be at least one case report of peripheral neuropathy but there is also a report of using lithium to treat peripheral neuropathy, although it's in a rat model of the illness, not in humans.  

A level of 1.2 is not necessarily too high, but it's right near the top; usually we use "trough" levels to determine what is the maximal acceptable, and different doc's use different maxima: 1.0 is too much for some patients, but some doctors will use 1.2 as "no higher than this" level.  

Dr. Phelps
 
 

Published February, 2002