A nurse is assessing a client who is experiencing acute amphetamine toxicity. Which of the following findings should the nurse expect?

A. Tachycardia: Amphetamines are central nervous system stimulants that increase sympathetic nervous system activity. Tachycardia is a common manifestation of acute toxicity, along with hypertension, hyperthermia, and agitation. Monitoring cardiovascular status is essential to prevent complications. B. Headache: While headaches can occur with amphetamine use, they are not a primary or consistent finding in acute toxicity. More prominent signs are cardiovascular and neurological stimulation rather than mild symptoms like headache. C. Increased appetite: Amphetamines typically suppress appetite rather than increase it. Clients experiencing acute toxicity are more likely to have decreased hunger due to stimulant effects on the hypothalamus. D. Pupil constriction: Amphetamines usually cause mydriasis (pupil dilation) due to sympathetic stimulation. Pupil constriction is more characteristic of opioid toxicity rather than amphetamine toxicity.