What is it?
Methamphetamine is a strong stimulant, typically smoked, snorted or injected. Effects last considerably longer than many other stimulants.
Common forms
- Crystals
- Powder
- Tablets
How it affects the body
It produces a strong and sustained increase in dopamine and noradrenaline activity, with pronounced effects on sleep, appetite and mood.
Short-term effects
- Intense stimulation and wakefulness
- Reduced appetite
- Raised heart rate and temperature
- Agitation and paranoia
Long-term effects
- Severe sleep disruption
- Dental and skin problems
- Psychosis
- Cardiovascular harm
- Dependence
Dependence and addiction
Dependence can develop when the body and brain adapt to regular use. It is not a moral failing or a lack of willpower. Signs people describe include needing more to get the same effect, difficulty cutting down, spending more time thinking about use, and continuing despite harm. Support is available at any stage — you do not need to have reached a crisis point.
Withdrawal
Stopping or reducing after regular use can cause withdrawal. Withdrawal varies between people and depends on how much and how long someone has used, their physical health and other substances involved. Some withdrawal can be medically serious, so it is safer to plan a reduction with a clinician or a drug and alcohol service rather than stopping abruptly alone. Extended fatigue, low mood and strong cravings are frequently described.
Overdose risks
Seizures, chest pain, extremely high temperature, stroke symptoms or collapse are emergencies. Call 999.
Mixing substances
Combining with other stimulants raises cardiovascular risk; combining with sedatives or opioids can mask overdose signs.
Harm-reduction information
- Avoid using alone
- Do not share injecting or smoking equipment
- Plan for sleep, food and fluids
- Sexual-health support is relevant where use and sex overlap — local services can help without judgement
When to seek urgent medical help
Call 999 if someone is unconscious or cannot be woken, is having difficulty breathing, has a seizure, has chest pain, becomes very confused or agitated, or you are worried they may have overdosed. For urgent advice that is not life-threatening, call NHS 111. You will not get someone into trouble by calling for medical help.
Treatment and recovery options
- Talking therapies and structured psychosocial support
- Community drug and alcohol services, including self-referral where available
- Medication-assisted treatment where clinically appropriate
- Medically supported withdrawal, arranged and monitored by clinicians
- Peer support and recovery communities
- Residential rehabilitation for some people, usually via assessment
- Support for related needs — mental health, housing, family and welfare
UK support resources
- NHS — health information and service finders (nhs.uk)
- Talk to FRANK — UK drug information service (talktofrank.com)
- Your local community drug and alcohol service — many accept self-referrals
- Local pharmacy teams, who can offer advice and signposting
Sources / references
This page is a plain-language summary written for education. For clinical or legal detail, use authoritative UK sources: NHS (nhs.uk), Talk to FRANK (talktofrank.com), NICE (nice.org.uk), UK Government and devolved government publications, and guidance from UK professional bodies. Each page on this site carries a review date, and we welcome corrections.