SUPERVISIÓN Y EVALUACIÓN DE LA IMT

benzodiazepine

abuse tripled

between 1998 and

2008.

sedation The induction of a calm, relaxed, often sleepy state.

tranquilizer A CNS depressant that reduces tension and anxiety.

stimulant A drug that increases nervous or muscular activity.

but do not measurably alter a normal, rested person’s ability to perform tasks calling for challenging motor skills or com- plex thinking. When amphetamines improve performance, it is primarily by counteracting fatigue and boredom. In small doses, amphetamines increase heart rate and blood pressure and change sleep patterns.

Amphetamines are sometimes used to curb appetite, but after a few weeks the user develops tolerance and higher doses are necessary. When people stop taking the drug, their appetite usually returns, and they gain back the weight they lost.

ABUSE AND ADDICTION Much amphetamine abuse begins as

an attempt to cope with a temporary situation. A student cramming for an exam or an exhausted long-haul truck driver can go a little longer by taking amphetamines. Th e likelihood of making bad judgments signifi cantly increases. Th e stimu- lating eff ects may also wear off suddenly, and the user may precipitously feel exhausted or fall asleep (“crash”).

Another problem is state dependence, the phenomenon whereby information learned in a certain drug-induced state is diffi cult to recall when the person is not in that same phys- iological state. Performance may deteriorate when students use drugs to study and then take tests in their normal, non- drug state.

Repeated use of amphetamines, even in moderate doses, often leads to tolerance and the need for increasingly larger doses. Th e result can be severe disturbances in behavior, in- cluding delusions of persecution and episodes of unprovoked violence.

Methamphetamine is more addictive than other forms of amphetamine. It also is more dangerous because it is more toxic and its eff ects last longer. In the short term, meth can cause rapid breathing, increased body temperature, insomnia, tremors, anxiety, and convulsions. Meth use has been linked to high-risk sexual behavior and increased rates of STDs, in- cluding HIV infection. In the long term, the eff ects of meth can include weight loss, severe acne, hallucinations, paranoia, violence, and psychosis. Meth use causes extensive tooth decay and tooth loss, a condition referred to as “meth mouth.” Meth takes a toll on the user’s heart and can cause heart attack and stroke. Methamphetamine users have signs of brain damage similar to those seen in Parkinson’s disease patients that ap- pear to persist even after drug use ceases, causing impaired memory and motor coordination. Withdrawal from meth causes symptoms that may include muscle aches and tremors, profound fatigue, deep depression, despair, and apathy. Addic- tion to methamphetamine is associated with pronounced psy- chological cravings and obsessive drug-seeking behavior. Women who use amphetamines during pregnancy risk premature birth, stillbirth, low birth weight, and early infant and therefore fast, intense eff ects. Another method of use

involves processing cocaine with baking soda and water, yielding the ready-to-smoke form of cocaine known as crack. Crack is typically available as small beads or pellets smokable in glass pipes.

EFFECTS Th e eff ects of cocaine are usually intense but short-

lived. Th e euphoria lasts from 5 to 20 minutes and ends abruptly, to be replaced by irritability, anxiety, or slight de- pression. When cocaine is absorbed via the lungs by either smoking or inhalation, it reaches the brain in about 10 sec- onds, and the eff ects are particularly intense. Th is is part of the appeal of smoking crack. Th e eff ects from IV injections occur almost as quickly—in about 20 seconds. Since the mu- cous membranes in the nose briefl y slow absorption, the on- set of eff ects from snorting takes 2–3 minutes. Heavy users may inject cocaine intravenously every 10–20 minutes to maintain the eff ects.

Th e larger the cocaine dose and the more rapidly it is ab- sorbed into the bloodstream, the greater the immediate— and sometimes lethal—eff ects. Sudden death from cocaine is most commonly the result of excessive CNS stimulation that causes convulsions and respiratory collapse, irregular heart- beat, extremely high blood pressure, blood clots, and possibly heart attack or stroke. Although rare, fatalities can occur in healthy young people; among people aged 18–59, cocaine us- ers are seven times more likely than nonusers to have a heart attack. Chronic cocaine use produces infl ammation of the nasal mucosa, which can lead to persistent bleeding and ul- ceration of the septum between the nostrils. Th e use of co- caine may also cause paranoia and aggressiveness. When steady cocaine users stop taking the drug, they experience a sudden “crash” characterized by depression, agitation, and fatigue, followed by a period of withdrawal .

COCAINE USE DURING PREGNANCY A woman who uses co-

caine during pregnancy is at higher risk for miscarriage, pre- mature labor, and stillbirth. She is more likely to deliver a low-birth-weight baby who has a small head circumference. Her infant may be at increased risk for defects of the genito- urinary tract, cardiovascular system, central nervous system, and extremities. It is diffi cult to pinpoint the eff ects of co- caine because many women who use cocaine also use tobacco and/or alcohol.

Infants whose mothers use cocaine may also be born in- toxicated. Cocaine also passes into breast milk and can in- toxicate a breastfeeding infant.

Amphetamines Amphetamines (uppers) are a group of synthetic chemicals that are potent CNS stimulants. Some common drugs in this family are amphetamine (Benzedrine), dextroamphetamine (Dexedrine), and methamphetamine (Methedrine). Crystal methamphetamine (also called ice) is a smokable, high-potency form of methamphetamine, or meth.

EFFECTS Small doses of amphetamines usually make people

feel more alert. Amphetamines generally increase motor activity

state dependence A situation in which

information learned in a drug-induced state is diffi cult to recall when the eff ect of the drug wears off .

R E P R E S E N T A T I V E P S Y C H O A C T I V E D R U G S 155 tions depends on the THC content and varies widely. Mari- juana plants that grow wild often have less than 1% THC in their leaves. When selected strains are cultivated by separation of male and female plants ( sinsemilla ), the bud leaves from the fl owering tops may contain 7–8% THC. Hashish, a potent preparation made from the thick resin that exudes from the marijuana leaves, may contain up to 14% THC.

Th ese various preparations have all been known and used for centuries, so the frequently heard claim that today’s mari- juana is more potent than the marijuana of the 1970s is not death. Babies born to amphetamine-using mothers have a

higher incidence of cleft palate, cleft lip, and deformed limbs. Th ey may also experience symptoms of withdrawal.

Ritalin A stimulant with amphetamine-like eff ects, Rit- alin (methylphenidate) is used to treat attention-defi cit/ hyperactivity disorder (ADHD). When taken orally at pre- scribed levels, it has little potential for abuse. When injected or snorted, however, dependence and tolerance can rapidly result.

Caff eine Caff eine is probably the most popular psychoac- tive drug and also one of the most ancient. It is found in cof- fee, tea, cocoa, soft drinks, headache remedies, and OTC preparations like NōDōz. (Table 7.3 lists typical levels of caf- feine in several popular beverages.) In ordinary doses, caf- feine produces greater alertness and a sense of well-being. It also decreases feelings of fatigue or boredom, so using caf- feine may enable a person to keep at physically tiring or re- petitive tasks longer. Such use is usually followed, however, by a sudden letdown. Caff eine does not noticeably infl uence a person’s ability to perform complex mental tasks unless fa- tigue, boredom, or other factors have already aff ected normal performance.

Caff eine mildly stimulates the heart and respiratory sys- tem, increases muscular tremor, and enhances gastric secre- tion. Higher doses may cause nervousness, anxiety, irritability, headache, disturbed sleep, and gastric irritation or peptic ul- cers. In people with high blood pressure, caff eine can cause blood pressure to rise even further above normal; in people with type 2 diabetes, caff eine may cause glucose and insulin levels to rise after meals.

Drinks containing caff eine are rarely harmful for most people, but some tolerance develops, and withdrawal symp- toms of irritability, headaches, and even mild depression oc- cur.. People can usually avoid problems by simply decreasing their daily intake of caff eine.

ENERGY “SHOTS” Th e popularity of small (1.5–3 oz) energy

drinks has increased dramatically in recent years. Worldwide sales of products such as 5-Hour Energy reached $9 billion in 2011. Because these products are sold as dietary supple- ments rather than food, their caff eine content is not regulated by the Food and Drug Administration. Each 2-oz “shot” typi- cally contains the same amount (roughly 100 mg) of caff eine as a regular-size cup of coff ee.

Marijuana and Other