Monday, June 13, 2005

Methamphetamine use and strokes

When working as a hospitalist a few weeks ago, I posted this about a woman I admitted who couldn't speak and had a decreased level of consciousness. Her intitial CT scan was negative, but over the next few days showed an evolving stroke. Her only risk factor was that she used tobacco and her drug screen revealed amphetamine use.

Methamphetamine is commonly known as "speed," "meth," and "chalk." In its smoked form, it is often referred to as "ice," "crystal," "crank," and "glass." It is a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol. The drug was developed early in this century from its parent drug, amphetamine, and was used originally in nasal decongestants and bronchial inhalers. Methamphetamine's chemical structure is similar to that of amphetamine, but it has more pronounced effects on the central nervous system. Like amphetamine, it causes increased activity, decreased appetite, and a general sense of well-being. The effects of methamphetamine can last 6 to 8 hours. After the initial "rush," there is typically a state of high agitation that in some individuals can lead to violent behavior.

Methamphetamine comes in many forms and can be smoked, snorted, orally ingested, or injected. The drug alters moods in different ways, depending on how it is taken.

Immediately after smoking the drug or injecting it intravenously, the user experiences an intense rush or "flash" that lasts only a few minutes and is described as extremely pleasurable. Snorting or oral ingestion produces euphoria - a high but not an intense rush. Snorting produces effects within 3 to 5 minutes, and oral ingestion produces effects within 15 to 20 minutes.

As with similar stimulants, methamphetamine most often is used in a "binge and crash" pattern. Because tolerance for methamphetamine occurs within minutes - meaning that the pleasurable effects disappear even before the drug concentration in the blood falls significantly - users try to maintain the high by binging on the drug.

In the 1980's, "ice," a smokable form of methamphetamine, came into use. Ice is a large, usually clear crystal of high purity that is smoked in a glass pipe like crack cocaine. The smoke is odorless, leaves a residue that can be resmoked, and produces effects that may continue for 12 hours or more.

Methods of use varies with the region of the country. Where I am, in east TN, the major route of use is smoking, although injection is on the rise. When I lived in San Diego, we saw more IV use.

Methamphetamine use has multiple medical complications, including a variety of cardiovascular problems. These include rapid heart rate, irregular heartbeat, increased blood pressure, and irreversible, stroke-producing damage to small blood vessels in the brain. Hyperthermia (elevated body temperature) and convulsions occur with methamphetamine overdoses, and if not treated immediately, can result in death.

Chronic methamphetamine abuse can result in inflammation of the heart lining, and among users who inject the drug, damaged blood vessels and skin abscesses. Methamphetamine abusers also can have episodes of violent behavior, paranoia, anxiety, confusion, and insomnia. Heavy users also show progressive social and occupational deterioration. Psychotic symptoms can sometimes persist for months or years after use has ceased.

Acute lead poisoning is another potential risk for methamphetamine abusers. A common method of illegal methamphetamine production uses lead acetate as a reagent. Production errors therefore may result in methamphetamine contaminated with lead. There have been documented cases of acute lead poisoning in intravenous methamphetamine abusers.

Fetal exposure to methamphetamine also is a significant problem in the United States. At present, research indicates that methamphetamine abuse during pregnancy may result in prenatal complications, increased rates of premature delivery, and altered neonatal behavioral patterns, such as abnormal reflexes and extreme irritability. Methamphetamine abuse during pregnancy may be linked also to congenital deformities.

Use of amphetamines and their derivatives are independent risk factors for development of stroke. Ischemic and hemorrhagic strokes are associated with the use of amphetamines. Methamphetamine is the most common form of illicit amphetamine in use. Like cocaine, it can be snorted, injected, or smoked, and is addictive. The pathophysiology is similar to cocaine and other sympathomimetics, including vasospasm, increased platelet aggregation, acute hypertension, cardiac dysrhythmias, embolization caused by infective endocarditis, embolization secondary to foreign material injected, vasculitis, adn exacerbation of pre-existing vascular disease. However, like drug-use-associated myocardial infaction, these patients commonly present without any pre-existing risk or disease.

Info gleaned and copied/utilized from here and Klausner, HA-Emerg Med Clin North Am- 01-Aug-2002; 20(3):657-70.