Methamphetamine-induced Encephalopathy in the Absence of Hyperammonemia

BackgroundMethamphetamine is an addictive drug with various effects on the neurotransmitters in the central nervous system. Methamphetamine-induced encephalopathy in the absence of hyperammonemia presents a unique challenge in a clinical setting. Previously published cases of methamphetamine-induced encephalopathy suggested that methamphetamine-induced hepatotoxicity and subsequent hyperammonemia may be the cause of encephalopathy. However, the literature is limited on methamphetamine-induced encephalopathy without hyperammonemia.CaseThis case presents a disoriented patient with methamphetamine use disorder in acute toxicity, unable to ambulate independently, and poorly responsive to verbal stimuli. The patient was found to have normal ammonia levels.DiscussionThis patient's presentation and laboratory findings, namely normal ammonia levels, suggest a different pathophysiological pathway for methamphetamine-induced encephalopathy. One potential pathway is through the direct action of methamphetamine on the central nervous system through acute disruption of neurotransmitter signaling and disruption of the blood-brain barrier.ConclusionFurther research should be conducted into the prevalence and pathophysiology of methamphetamine-induced encephalopathy in the absence of hyperammonemia.