HepCInfo.ca | PositiveSide.ca | LivePositive.ca | TreatHIVGlobally.ca | Resources for Nurses

TreatmentUpdate 149

Volume 17 Issue 3

2005 April/May

6. ADDICTIONS: Drug twists brain and body

Crystal meth (crystal methamphetamine) goes by several other names, including the following:

tina
ice
meth
crystal

Because it is part of the amphetamine group of drugs, crystal meth has a stimulating effect and, like all amphetamines, can affect the heart and cardiovascular system, causing the following complications:

rapid heart beats
high blood pressure
short, rapid breaths
feeling hot

Repeated, regular use of crystal meth (bingeing) can cause inflamed blood vessels and heart damage. All of this can lead to other complications, including strokes and high blood pressure. These complications have been noted in relatively young people not normally at risk for cardiovascular disease but who became at risk due to exposure to crystal meth.

Kidneys and muscles
Crystal meth has also been found to cause muscle breakdown, leading to kidney damage. In one study of people who sought help from the Emergency departments of California hospitals, researchers found that 43% of patients with muscle breakdown and kidney damage had crystal meth in their urine samples.

Infection and immunity
In laboratory experiments, crystal meth appears to weaken a key group of cells of the immune system, CD8+ cells. They are responsible for fighting infections, including HIV.

In one study, long-term use of crystal meth was associated with an increase in gum disease. The stimulation and agitation caused by crystal meth was likely responsible for participants in that study having partially worn down their teeth by clenching and grinding their jaws.

No regulation
Because regulatory agencies do not monitor or assess the production, purity and safety of crystal meth, it is not surprising that batches of this drug can be contaminated with other compounds. The production of crystal meth is a toxic affair and lead poisoning has been reported in some users.

Juggling drugs
Crystal meth and chemically related compounds such as ecstasy are broken down by enzymes in the intestine and liver. Two classes of anti-HIV medications are also processed by these same enzymes:

protease inhibitors (PIs)
non-nukes (non-nucleoside reverse transcriptase inhibitors)

When two different compounds are processed simultaneously through the same enzyme, levels of one or both drugs can either rise or fall, leading to increased side effects or drug resistance. In the case of crystal meth, PIs and non-nukes have the potential to increase levels of this drug to very high levels. At least one person has died because of this interaction.

Crystal on the brain
Perhaps the most disturbing and obvious impact of long-term exposure to crystal meth is its many effects on the brain. Experiments on rats suggest that the concentration of crystal meth in the brain is about 10 times greater than that found in the blood after the animals have been given the drug. In people, crystal meth appears to last a relatively long time, with 50% of the drug being detectable 12 hours after a dose was taken. These findings suggest that meth concentrates in the brain and likely lasts a relatively long time in this organ. Thus the brain may bear the brunt of crystal meth’s toxic effects.

Cells in the brain use compounds called neurotransmitters, including serotonin and dopamine, to send signals to each other. These compounds also play a role in many functions, including memory, mood, muscle control and learning.

In one study of 15 HIV negative, long-term crystal meth users, researchers scanned their brains with hi-tech PET scanners. The scans revealed less-than-normal levels of molecules used to move the neurotransmitter dopamine to cells. This likely reduced the ability of brain cells to get access to dopamine and possibly affected their ability to store and retrieve information as well as control muscles. Not surprisingly, further research found that the participants had difficulty learning and coordinating the movement of their muscles.

HIV and crystal meth
Based on the results of test-tube and animal experiments, some researchers suggest that crystal meth has the potential to make HIV-related brain damage worse. Possibly, the mixture of crystal meth and toxic proteins produced by HIV could increase the risk of AIDS-related problems involving clear thinking and memory. But long-term studies of HIV positive crystal meth users are needed to confirm this theory.

Crystal enters the body
There are many ways in which this substance can enter the body. Crystal meth can be:

snorted
swallowed
injected into blood vessels
squirted into the rectum

Depending on which method is chosen, the high from crystal meth can occur anywhere from one to 20 minutes after the drug is taken. Initially, users have reported the following feelings:

a heightened sense of alertness
euphoria
an increased sense of well-being and confidence

But doctors have also observed other, less glamourous effects of crystal meth in users, such as:

personality changes
restlessness
tension
irritability
problems falling asleep
loss of appetite
unintentional weight loss
verbally threatening and sometimes physically aggressive behaviour

Because 50% of crystal meth leaves the body within 12 hours of being taken, its pleasurable effects can wane within this time frame. Users often take another hit of the drug to avoid the following symptoms of withdrawal:

depression
lack of energy
loss of pleasure from everyday activities
thoughts of suicide

The downward spiral
Continued use of crystal meth over several days can lead to an “extremely irritable and paranoid state,” according to researchers. What’s more, in about 10% of long-term users, exposure to this drug can lead to a state of psychosis with the following features:

feelings of paranoia
disconnection from reality
intense hallucinations

Recovery
Crystal meth users who enter treatment programs appear to recover from some effects of this drug. For instance, in a study of 170 crystal meth users, 23% reported feelings of paranoia when they entered a treatment program. Between two and five years after completing the program, only 7% still had feelings of paranoia.

Sadly, 62% of 170 participants were depressed when they entered the program and the same proportion remained depressed when they left. And 28% of participants reported violent behaviour in the year after they had left the program, according to the research team. Overall, these findings suggest that cystal meth exposure can cause lasting damage in some people.

Crystal meth impairs the brain’s ability to make and possibly use the neurotransmitter dopamine, and HIV appears to damage dopamine-producing parts of the brain. Some doctors who treat people with HIV/AIDS (PHAs) recovering from meth addiction have found the antidepressant bupropion (Wellbutrin, Zyban) useful for managing depression in their patients. Because antidepressants take weeks or even months to begin to work, these drugs are not suitable for treating withdrawal from substance use. Many other compounds are being tested for their anti-addiction effects in crystal meth users, including anti-schizophrenia medicines. And, of course, medication(s) are used together with different forms of counseling, 12-step programs and harm reduction messages to help people begin the process of healing and recovering their lives from substance use.

REFERENCES:

1. Langford D, Grigorian A, Hurford R, et al. The role of mitochondrial alterations in the combined toxic effects of human immunodeficiency virus Tat protein and methamphetamine on calbindin positive-neurons. Journal of Neurovirology 2004;10(6):327-337.

2. Chang L, Ernst T, Speck O and Grob CS. Additive effects of HIV and chronic methamphetamine use on brain metabolite abnormalities. American Journal of Psychiatry 2005;162(2):361-369.

3. Semple SJ, Patterson TL, Grant I. A comparison of injection and non-injection methamphetamine-using HIV positive men who have sex with men. Drug and Alcohol Dependence 2004;76(2):203-212.

4. Urbina A, Jones K. Crystal methamphetamine, its analogues, and HIV infection: medical and psychiatric aspects of a new epidemic. Clinical Infectious Diseases 2004;38(6):890-894.

Created on: 2005 June 6

Author: Hosein SR

CATIE-News

What's New?

CATIE Publications

Decisions about particular medical treatments should always be made in consultation with a qualified medical practitioner who is knowledgeable about HIV-related illness and the treatments in question. MORE

Privacy | Permission to reproduce | Funders

Production of this Web site has been made possible through a financial contribution from the Public Health Agency of Canada.