Relevance to Psychiatry:
DEPAKOTE - Valproate can elevate ammonia levels
Hyperammonemia is a cause of delirium
Symptom of high ammonia: encephalopathy --> delirium, sedation, slow mentation
Reference range (normal) ammonia level:
Sermo: What is the standard of care for handling hyperammonemia with Depakote? Physicians Only
Sermo: 46-y/o male Hep C cirrosis had ammonia > 200 but not confused. Lactulose only lowered to 180 Physicians Only
- Routine ammonia level is unnecessary, except elderly patients
- If AST normal ~4 and ~12 weeks, ammonia not necessary
- BID dosing instead of HS?
- Get ammonia level and LFT's if encephalopathy is suspected (slow to develop: delirium, sedation, slow mentation)
- Mental slowing can be seen with Depakote without elevated ammonia
- If someone is delirious or encaphalopathic, consider stopping Depakote with or without ammonia levels
- Reduction in dose reduces ammonia levels
- Consider LAMICTAL - lamotrigine (but Depakote better for Intermittent Explosive Disorder)
- Non-fasting ammonia levels can be misleading
- Needs 1-2 loose bowel movements daily
- Low protein diet
- Can add rifaximin 200mg tid
- "Why are you chasing the ammonia level if you believe he is not encephalopathic?"
- "Treat the patient, not the numbers."
- EEG to assess encephalopathy
- "Ammonia levels are notoriously inaccurate and should be rarely obtained outside of a research setting."
Do you stop the Depakote?
Noted from Am J Psychiatry 164:7, July 2007:
The results of the prospective study found a reduction in divalproex dose always resulted in a reduction in ammonia levels.
The authors conclude that complete withdrawal of divalproex is necessary in only the most severe cases of side effects.