Methamphetamine use stimulates the brain and central nervous system, and can result in a variety of adverse outcomes. The effect that methamphetamine has on an individual depends on a number of factors. These include:

• how much methamphetamine is taken
• the method of use
• the form and purity of the methamphetamine
• the height and weight of the user
• the user’s current physical and mental health status
• the user’s previous experience with methamphetamine (i.e. new user vs frequent user)
• whether other substances (alcohol, tobacco, medications, or other illicit drugs) are used at the same time as methamphetamine.

There are a variety of physical health risks associated with methamphetamine use. Many of these risks are very serious, and can result in severe short- and long-term consequences for the user.

The effects of methamphetamine are the same regardless of which form (e.g. powder/base/crystal) is used. However, crystal methamphetamine (ice) tends to be more potent and purer than other forms. As a result, the effects of ice are both more likely to occur and likely to be more intense than when other forms of methamphetamine are used.

Short-term effects

The short-term physical effects of using methamphetamine include:

• increased or irregular heart rate (palpitations)
• chest pains
• breathing faster or irregularly
• loss of appetite
• high blood pressure
• dilated pupils
• increased perspiration
• feeling restless, shaky, or moving more quickly
• sleeplessness
• jaw clenching or teeth grinding
• headaches
• dizziness
• pale complexion
• elevated body temperature
• nausea, vomiting or diarrhoea
• seizures.

If a large and/or strong batch of methamphetamine is taken, an overdose may occur. Overdoses can involve:

• racing heart
• seizures
• passing out
• stroke
• heart attack
• death.

Long-term effects

If methamphetamine is used regularly for an extended period of time, long-term physical effects can include:

• weakened immune system
• stroke
• heart infection
• lung disease
• kidney and liver damage
• poor dental health
• poor dietary intake and extreme weight loss
• restless sleep
• regular colds and flu
•  muscle stiffness
• skin lesions and infections.

The way in which methamphetamine is used can further impact on the health of the user. For instance:

• Snorting methamphetamine can lead to nosebleeds, sinus problems, and damage to the inside of the nose.
• Injecting methamphetamine with unsterile or shared equipment increases the risk of contracting blood borne viruses (HIV, hepatitis B and C), blood poisoning (septicaemia), tetanus, or skin abscesses.
• Injecting methamphetamine can also result in blocked blood vessels, leading to inflamed blood vessels, abscesses, and serious damage to the liver, heart, or kidneys.

For more information about the effects of methamphetamine, see FAQs What are the effects of methamphetamine use? and What are the mental health risks of methamphetamine use?