Meth is short for methamphetamine, which is a potent stimulator of the central nervous system. It is sometimes called speed, ice, glass, and crystal meth.

The term “crystal meth” in particular, usually refers to methamphetamine that is smoked or injected, resulting in a particularly rapid and potent “high.” Meth, a white powder, can also be swallowed and snorted.

It is important to realize that there are some medical uses for methamphetamine, but given the high risk of abuse and side effects, it is prescribed sparingly and should be used with extreme caution.

Short Term Effects

Like other stimulant drugs, meth produces euphoric feelings by hijacking the dopamine reward pathway in the brain.

Instead of getting a small drop of dopamine released when we have a nice meal or get a hug from a loved one, meth releases huge amounts of dopamine, which gives the intense sensation of pleasure.

Methamphetamine increases alertness, wakefulness, energy, and suppresses appetite. These are more likely to occur with swallowed methamphetamine.

  • Smoking meth causes an intense “high” similar to injection.
  • Swallowed meth takes longer to act on the brain and the pleasurable sensations are not as intense.

Short term intoxication by any route of administration causes an increased heart rate, blood pressure, and blood sugar.

Short Term Damage of Meth

Because meth strongly affects the reward system of the brain and the dopamine system, there is a narrow window between therapy and abuse.

This is of special concern for those who are prescribed amphetamines.

Fortunately the doses used clinically are generally far less than the blood levels achieved by those that abuse meth. This means those that take the drug as directed are less likely to experience the drug’s negative effects than those that abuse it.

Nevertheless there is a high potential for those that use amphetamines to crave the drug and eventually become addicted to it.

It is also important to note that meth can increase libido and delay ejaculation, which are perceived benefits to some users.

Methamphetamine use is emerging as a growing and independent risk factor for risky sexual behavior and HIV transmission.

Long Term Damage

While there are some short term risks with meth use, the most damaging effects occur over the course of chronic use.

Repeatedly interfering with the dopamine system has consequences.

  • Abusers have actual brain damage in the dopamine system.
  • This causes mood, emotional, and cognitive disturbances.
  • Users have trouble forming and recalling memories especially those that have an emotional component (e.g. a touching family reunion).

Using methamphetamine for long periods of time may lead to:

  • Extreme weight loss
  • “Meth mouth” (severe tooth decay associated with meth use)
  • Chronic anxiety and insomnia
  • Mood disturbances (e.g. depression)
  • Violent behavior
  • Psychosis (hallucinations, delusions, paranoia)


Meth affects the body as well as the brain because of its effect on dopamine. Meth can have direct effect on the heart.

In high doses this can lead to:

  • Cardiomyopathy (heart muscle damage)
  • Pulmonary edema (fluid in the lungs)
  • Kidney failure
  • Myocardial infarction (heart attack)
  • Stroke

Meth overdose can also cause death.

Symptoms and Signs of Abuse

Since methamphetamines are stimulants, early signs of abuse may run counter to what many would think of someone abusing drugs.

Instead of being withdrawn and moody, oral methamphetamine abusers might actually be very high functioning due to the increased alertness and concentration.

In fact, many users first start in order to get an edge in class work or on their jobs. Over time the body becomes dependent on the stimulant and more of the drug is required to achieve the desired effect.

Abusers may experiment with other routes of administration, like snorting.

Meth abuse can sometimes be identified due to:

  • Unexplained weight loss
  • Anxiety
  • Mood disorder
  • Trouble sleeping
  • “Meth mouth” or a rapid decline in oral health

Methamphetamine can be synthesized in homemade laboratories (aka “meth lab”) using components that are found at the drug store or other retail outlets.

Unexplained lab equipment like hot plates, glass beakers and tubes, and small electronic scales are a huge red flag.

“Cooking meth” is incredibly dangerous since it requires the use of volatile and explosive chemicals. If you think you have found a meth lab, do not investigate the area further and report the site to law enforcement immediately.

Adverse Interactions

Meth is often abused with other stimulants, such as MDMA (ecstasy). Thus the serotonin system is altered along with dopamine. The net effect is that mood disturbances, especially anxiety and depression, come on more quickly and more severely.

Meth is especially dangerous when taken with tricyclic antidepressants. Insulin and diabetes medication may be affected because of meth’s increase in blood sugar. Also, the effects and side effects of corticosteroids (like prednisone) are intensified when one uses methamphetamine.


Find a rehab that specializes in treating a meth addiction.



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