Patients w/ latent & overt neuromuscular disease, particularly Duchenne muscular dystrophy. Risk of malignant hyperthermia may be increased in patients w/ hypersensitivity to volatile halogenated anesth agents; concomitant use w/ K hydroxide containing CO2 absorbents. Risk of seizures. Patients w/ underlying hepatic conditions or under treatment w/ drugs known to cause hepatic dysfunction. Premature infants. Pregnancy & lactation.