Valproic acid-induced encephalopathy in very long course treated patients.
OBJECTIVE
In patients receiving valproate (VPA) treatment, valproate induced-encephalopathy (VIE) is among the most serious adverse side-effects and hyperammonaemia is a frequent and well-recognized event. This report evaluates adult patients receiving VPA for several years.


METHODS
This study was conducted in adult patients receiving VPA for several years. Many studies have evaluated blood ammonia levels and VPA-related encephalopathy in patients whose treatment was initiated for a few months. Most studies were conducted in children.


METHODS
This study looked at retrospectively occurrences of VIE in 63 patients who were receiving VPA for a minimum duration of at least 2 years. At the beginning of the study basal ammonaemia was measured for all patients.


RESULTS
This study reports a rather frequent onset of VIE. Long duration of VPA treatment was not correlated with encephalopathy onset. In seven cases temporary administration of lactulose alone was effective and VPA was continued.


CONCLUSIONS
This study confirms that, under VPA treatment, hyperammonaemia is a current event; 25.4% patients presented isolated elevated ammonaemia when receiving VPA for very long durations. VPA therapy should be monitored closely and clinicians must be warned of VPA encephalopathy signs.
Rousseau
Marie-Christine
MC
Hôpital San Salvadour (Assistance Publique Hôpitaux de Paris), Hyères cedex, France. marie-christine.rousseau@ssl.aphp.fr
Montana
Marc
M
Villano
Philippe
P
Catala
Anne
A
Blaya
José
J
Valkov
Maria
M
Allouard
Yves
Y
Bugni
Estelle
E
D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000009:adverse effects*; D001925:Brain Damage, Chronic / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006501:Hepatic Encephalopathy / Q000139:chemically induced*; D006801:Humans; D022124:Hyperammonemia / Q000139:chemically induced*; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014635:Valproic Acid / Q000009:adverse effects*; D055815:Young Adult
D000927:Anticonvulsants; D014635:Valproic Acid