Methamphetamine is a powerful synthetic stimulant that is illegal, highly addictive, and very dangerous to health. Its prevalence and associated harms have risen sharply across Canada over the past decade. The Canadian Centre on Substance Use and Addiction notes that since 2013 there has been a dramatic increase in the availability and harms associated with methamphetamine in Canada, particularly in British Columbia, Alberta, Saskatchewan, and Manitoba.
The scale of that increase is visible in clinical settings. At CAMH in Toronto, for example, the number of people visiting the Emergency Department due to amphetamine use (predominantly methamphetamine) increased by more than 700 per cent between 2014 and 2021. What was once a relatively uncommon substance in much of the country has become a serious and growing concern, and Canada’s treatment system is still working to respond.
What Is Methamphetamine?
Methamphetamine is a synthetic stimulant drug belonging to the amphetamine family, a class of drugs that speed up the central nervous system. It is controlled under Schedule I of the Controlled Drugs and Substances Act, and pharmaceutical methamphetamine is not authorized in Canada, meaning any methamphetamine in circulation is illicitly produced. CAMH notes that it is made in illegal labs using fairly inexpensive, and often toxic or flammable, ingredients, with the chemicals and processes varying from lab to lab, affecting the strength, purity, and effect of the final product.
Methamphetamine appears in several forms. As a powder (often called “speed”), it can be snorted, swallowed, or dissolved and injected. In its crystal form, known as crystal meth, ice, tina, crank, or glass, it appears as transparent, sheet-like crystals and is typically smoked.
How quickly methamphetamine takes effect depends on how it is used. Health Canada notes effects are felt within seconds when injected or smoked, within three to five minutes when snorted, and within twenty to thirty minutes when swallowed. Effects typically last eight hours but can sometimes last up to twenty-four hours, significantly longer than those of cocaine.
How Methamphetamine Works in the Brain
Methamphetamine produces intense effects on the brain’s reward system, creating a surge of pleasure far beyond what everyday experiences produce. CAMH describes the result as an intense surge of euphoria, called a “rush” or “flash,” when the drug is smoked or injected. The drug also produces the physical stimulant effects users experience: elevated heart rate, blood pressure, and body temperature.
With chronic use, the brain can be progressively damaged. CAMH notes that research in animals and humans suggests methamphetamine may cause long-term damage to cells in areas of the brain associated with thinking, memory, and movement, though further research is needed to determine whether these effects are permanent. Health Canada adds that long-term use can impair the brain’s ability to produce chemicals it normally produces, affect a person’s ability to stay attentive, and cause short or long-term memory problems.
This damage to the brain’s chemistry is part of what makes stopping methamphetamine so difficult. People who have used it heavily over a long period often experience a prolonged period of depression, an inability to feel pleasure, and intense craving after they stop, because the brain needs time to restore its normal function.
Short-Term Effects
Desired Effects
Health Canada lists the desired effects of methamphetamine as euphoria, higher energy and less fatigue, increased wakefulness and alertness, a rapid flow of ideas and speech, elevated mood and confidence, increased libido, and decreased appetite. CAMH’s Straight Talk publication notes that people use methamphetamine because it gives them energy and makes them feel confident, alert, and strong for many hours.
Adverse Short-Term Effects
Even initial use can produce adverse effects, especially at higher doses or in sensitive individuals. These include restlessness and anxiety, paranoia, overheating of the body (which can be fatal during physical activity), elevated blood pressure with risk of stroke or cardiac arrest, irregular heartbeat, and seizures. CAMH’s Straight Talk notes that the combination of elevated blood pressure and body overheating during physical activity can create life-threatening situations.
Binge Effects and “Tweaking”
Some people use methamphetamine continuously over days in a “binge and crash” pattern. Health Canada describes the binge state as one where euphoria decreases over time while unpleasant effects and compulsive behaviour increase, including sleeplessness, paranoia, and hallucinations. The state that develops as effects wear off, known as “tweaking,” is described by Health Canada as particularly dangerous: a combination of intense drug craving, anxiety, sleeplessness, and irritability that can escalate to aggression, hostility, and a disconnection from reality.
Long-Term Health Effects
Neurological and Mental Health Effects
Health Canada identifies significant, sometimes permanent, neurological consequences of long-term methamphetamine use. These include brain damage affecting the ability to produce chemicals the brain normally produces, difficulty controlling impulses, difficulty staying attentive, and short and long-term memory problems. Behavioural consequences include high-risk sexual activities and long-lasting or permanent aggression. The risk of psychosis, including hallucinations, paranoid delusions, and loss of touch with reality, is among the most serious long-term effects. CAMH’s Straight Talk notes that for some people, using methamphetamine leads to feeling paranoid, becoming confused, angry, and violent.
Cardiovascular Effects
Health Canada identifies serious cardiovascular consequences of long-term use. Even young users can experience heart attack, stroke, sudden cardiac death, and a reduction of the heart’s ability to pump blood to the body.
Physical Health Effects
Additional long-term physical effects include severe malnutrition from appetite suppression and neglect of eating, a weakened immune system, and damaged skin including sores that if left untreated can become infected. CAMH describes what users call “meth bugs,” the feeling of bugs under the skin, which leads to skin-picking and sores. Methamphetamine mouth, severe dental decay and tooth loss, results from dry mouth, poor oral hygiene, and teeth clenching.
Methamphetamine Dependence
Methamphetamine is highly addictive. CAMH notes that tolerance to the effects builds up quickly in regular users, meaning they need more and more of the drug to achieve the desired effect. Health Canada adds that difficulty getting high causes great frustration and unstable behaviour.
CAMH’s Straight Talk publication describes the signs of methamphetamine addiction as having built up a tolerance, feeling irritable, depressed, or lacking energy when not taking it, spending so much time and money getting it that important responsibilities are neglected, constantly thinking about the next use, and continuing to use despite problems caused.
When someone stops using methamphetamine after regular use, withdrawal follows. Health Canada describes cravings so intense that a person cannot focus on anything else, along with intense fatigue, difficulty sleeping, constant hunger, an inability to feel pleasure, depression, anxiety, and irritability. CAMH adds that withdrawal can also include stomach pain, headaches, and shortness of breath. These symptoms can last weeks and drive a strong motivation to return to use.
Methamphetamine-Induced Psychosis
One of the most serious risks of methamphetamine use is its capacity to produce psychosis: a state of hallucinations, delusions, and disconnection from reality. CAMH notes that regular long-term use can develop into amphetamine psychosis, with hallucinations, delusions, paranoia, and bizarre and violent behaviour. Psychosis can also involve erratic or bizarre thought patterns and a complete loss of touch with reality.
Stimulant-induced psychosis can last days but usually resolves once the substance leaves the body. The scale of the problem is significant: at CAMH in Toronto, for example, nearly 50 per cent of youth visiting the Emergency Department and receiving outpatient care exhibit psychotic symptoms, though this reflects multiple contributing factors beyond methamphetamine alone.
Methamphetamine in Canada’s Drug Supply
Methamphetamine is closely tied to Canada’s broader drug poisoning crisis. CATIE reports that in 2021, methamphetamine was present in 55 per cent of stimulant toxicity deaths, and that 59 per cent of reported opioid toxicity deaths also involved a stimulant. People combine the two substances for a range of reasons, including prolonging euphoric effects, counteracting negative effects of one drug with the other, and avoiding opioid withdrawal.
Canada’s unregulated drug supply adds another layer of risk. CATIE notes that in British Columbia in 2018–19, fentanyl was found in 10 per cent of methamphetamine samples and 7 per cent of cocaine samples, compared with 3 per cent of stimulant samples nationally and 1 per cent of samples in Quebec. This means someone using what they believe is only methamphetamine may unknowingly be exposed to fentanyl, making naloxone and drug checking services important harm reduction tools even for people who do not intentionally use opioids.
Finding Help for Meth Addiction
Methamphetamine can cause serious harm, but recovery is possible. Treatment approaches exist that help people stop or reduce their use and manage withdrawal. If you or someone you care about is affected by methamphetamine use, reaching out to a physician, a counsellor, or a treatment or community program is a good first step. You can learn more about what treatment involves on our methamphetamine treatment page.