All of the following are recognised effects of amphetamines EXCEPT:

Correct answer: C. Orthostatic hypotension

• A. IS an effect. Beta-1 stimulation produces tachycardia, palpitations and arrhythmias — a central reason to avoid or strictly limit epinephrine-containing local anesthetic in a patient using amphetamines or methamphetamine.
• B. IS an effect. Sympathetic stimulation reduces salivary flow, producing xerostomia — a major contributor to the rampant caries pattern known as 'meth mouth,' along with bruxism, acidic drink consumption and neglect.
• C. CORRECT — this is the EXCEPTION. Amphetamines are indirect SYMPATHOMIMETICS that release and block reuptake of noradrenaline and dopamine. They raise blood pressure through alpha-mediated vasoconstriction. ORTHOSTATIC HYPOTENSION is the opposite effect and belongs to alpha-BLOCKERS, antihypertensives, tricyclics and antipsychotics.
• D. IS an effect. Amphetamines raise the metabolic rate and impair heat dissipation; hyperthermia is a recognised feature of amphetamine toxicity.

Note: ⚠️ The source keyed 'fever' as the exception. Hyperthermia is in fact a well-documented amphetamine effect, whereas orthostatic hypotension is genuinely inconsistent with their pharmacology. Please raise this with the group. Clinical rule: defer elective care for at least 24 hours after last use and avoid epinephrine.