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Methamphetamine (Meth)

What Is Methamphetamine?

Methamphetamine, or meth, is a powerful stimulant drug. It was originally developed for medical use. Doctors now know that long-term use can cause severe health and mental problems so it's not prescribed much anymore.

Methamphetamine usually comes in a crystal-like powder that is white or off-white, depending on how pure it is. Sometimes it is a small chunk of rock that flakes apart. The flakes can look like glass, which is how meth gets some of its nicknames. Meth is swallowed, snorted through the nose, smoked, or injected with a syringe.

Short-Term Effects

Meth gives people an energetic and "high" feeling. It works by increasing the levels of a chemical in the brain called dopamine, which carries messages between nerve cells in the brain. It's responsible for messages about motivation, pleasure, and motor skills.

When people smoke or inject meth, they feel a quick high that may only last a few minutes. Users who swallow or snort meth may not feel this rush, but will still get the rest of the drug's effects. After the first rush, a meth high is basically a state of agitation that can last up to 14 hours. During this time, users will have faster heart and breathing rates as well as higher blood pressure and body temperature. A meth high can cause people to behave unpredictably — even violently.

Large doses of methamphetamine can lead to a condition called hyperthermia, where the user's body temperature gets dangerously high. Hyperthermia can lead to convulsions and death if it is not treated immediately.

Other short-term effects include:

  • dilated pupils in the eyes
  • dry mouth
  • wakefulness and insomnia
  • irritability and aggression
  • anxiety and nervousness
  • decreased appetite

Long-Term Effects

Over time, the brain gets used to the increased levels of dopamine, so meth users build up a tolerance to the drug. This means users have to take more of the drug to feel the same highs. People can quickly get addicted to meth.

Long-term meth use can cause brain damage and severe mental problems, including paranoia, hallucinations, and delusions. Meth users often notice a feeling like insects are crawling around under their skin. Lots of meth users have open sores from scratching their skin away in an attempt to get at these "bugs" — even though they're not there.

The mental problems related to meth use can go on for years. Sadly, they may never go away, even after a user stops taking the drug.

One well-known effect of methamphetamine use is severe dental problems, also known as "meth mouth." Advanced tooth decay is common, which is why you see pictures of meth users with broken or rotten teeth.

Over time, meth use leads to a decrease in dopamine. Because dopamine controls a person's motor skills, users can get body tremors similar to those from Parkinson's disease.

Long-time meth users also can suffer from respiratory issues, organ damage, and high blood pressure. They may have heart problems like strokes, seizures, and heart failure.

Other long-term effects include:

  • anxiety and confusion
  • repetitive or compulsive activity
  • insomnia
  • personality changes
  • mood disturbances or psychotic behavior
  • memory loss
  • weight loss or anorexia
  • strange or violent behavior

Other Possible Problems

People can overdose on meth if they take too much at once. Signs of overdose are a high temperature, hallucinations, and convulsions. As with overdoses involving many other drugs, people who overdose on meth can die.

Meth users often go on binges, doing the drug every few hours over a number of days. This greatly increases all the dangers of meth use.

Also, meth's effects on dopamine can make people feel less inhibited and increase sexual feelings, making them more likely to have unsafe sex, which raises their risk of getting an STD. Users who inject meth also have a higher chance of getting AIDS or hepatitis from sharing needles.

Almost all methamphetamine is made in illegal laboratories. This is dangerous for the people making the drugs (the chemicals are harmful to humans and the environment), and also means that drug users have no way of knowing how strong the drug is or what else is in it.

Methamphetamine is listed as a Schedule II drug, meaning it has a high potential for abuse and very limited medical uses. Medical methamphetamine is only available through a doctor with a prescription that can't be refilled. Using or possessing meth without a prescription is punishable by fines and jail time.

How Can Someone Quit?

Because meth is so addictive, it can be very hard to quit. Users who try to quit can feel depression, anxiety, fatigue, and intense cravings for the drug. Often, meth addicts will go back on the drug even after a year or more of not using it.

Currently, there are no drugs approved for treating methamphetamine addiction. The most effective treatments are cognitive-behavioral programs that help drug addicts with counseling, support, and encouragement. A few treatment programs focus on giving rewards for staying off drugs.

If you think you could have a meth problem, talk with a counselor or join a support group. Anyone addicted to meth will need help quitting, so reaching out for support is an important first step.

Avoiding Meth

Methamphetamine can have some of the scariest side effects of any drug. You've probably seen images of meth addicts or seen or read about someone whose life was ruined. This is definitely a drug to avoid: Because quitting is so very hard, it's best to never try meth in the first place.

Date reviewed: February 2014

Note: All information on TeensHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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