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Recovery from amphetamine use follows a predictable pattern driven by catecholamine (dopamine and norepinephrine) depletion. The comedown begins as drug levels drop, peaking 8–16 hours after the last dose. Occasional users recover within 1–3 days, while chronic users may experience weeks of low energy, mood disturbance, and concentration difficulty as neurotransmitter systems rebalance.
The amphetamine comedown differs from the cocaine crash in important ways. Amphetamine's longer half-life (8–14 hours vs 30–90 minutes) produces a more gradual decline rather than an abrupt crash. The primary comedown symptoms are fatigue, increased appetite, low motivation, irritability, and disrupted sleep. Unlike cocaine, cravings during the amphetamine comedown are typically moderate rather than intense.
Sleep recovery is often the most noticeable challenge. Amphetamine suppresses sleep onset and reduces total sleep time. After cessation, 'rebound hypersomnia' can produce 12–16 hours of sleep for 1–3 nights. Sleep architecture (particularly slow-wave and REM sleep) may take 3–7 days to normalize for occasional users and 2–4 weeks for chronic users.
Appetite recovery follows a characteristic pattern: suppression during use → rebound hyperphagia (excessive hunger) during recovery. This rebound is driven by neuropeptide and hormonal changes (ghrelin, leptin) and typically lasts 3–7 days. Some chronic users gain significant weight during early recovery due to combined increased appetite and reduced energy expenditure.
Use this calculator as a starting point for any health or fitness goal that requires a numeric benchmark. The result is an estimate, not a diagnosis — but it provides a concrete figure to track against over time.
Many users apply adult health classifications to children and teenagers, which is incorrect. Paediatric norms for height, weight, BMI, and body composition are age-and-sex-specific. Use age-appropriate reference tools for anyone under 18.
A nurse calculates a patient's health metric during a routine assessment, then uses the result alongside other clinical indicators to contextualise the finding — correctly treating the number as one data point among several rather than a standalone answer.
4–12 hours for the acute comedown. Full energy and mood recovery: 1–3 days for occasional use, 1–4 weeks for chronic use. Sleep normalization takes 3–7 days.
Not typically medically dangerous, but the fatigue and mood disturbance can impair driving and work performance. Chronic users who stop abruptly may experience notable depression — seek professional support if this is severe.
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