Very infrequently, paradoxical reactions may occur, for example, excitement, stimulation, hallucinations, hyperactivity, and insomnia.
en.wikipedia.org In animal models, supplemental carnosine can increase corticosterone levels, which may explain the hyperactivity sometimes seen in high doses.
en.wikipedia.org Patients that present both megalencephaly and autistic characteristics usually also show signs of hyperactivity as a major symptom.
en.wikipedia.org These distinct symptoms in the absence of hyperactivity though were described in a separate category called sluggish cognitive tempo.
en.wikipedia.org The behavioural deficits caused include neophobia, a larger response to new stimulus, locomotor hyperactivity, and increased aggression.
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