Amphetamines dependence potential

The various stimulants have no obvious chemical relationships and do not share primary neurochemical effects, despite their similar behavioral effects. Cocaines chemical strucmre does not resemble that of caffeine, nicotine, or amphetamine. Cocaine binds to the dopamine reuptake transporter in the central nervous system, effectively inhibiting dopamine reuptake. It has similar effects on the transporters that mediate norepinephrine and serotonin reuptake. As discussed later in this chapter in the section on neurochemical actions mediating stimulant reward, dopamine is very important in the reward system of the brain the increase of dopamine associated with use of cocaine probably accounts for the high dependence potential of the drug. 

The patterns of anabolic-androgenic steroid use by sportspeople and body-builders, and their physical and psychological side-effects and dependence potential, have been very well reviewed by Brower (2002). Much of the use is by injection, and so many of this population attend needle exchanges, with the advice on reducing infection risks relevant. To increase energy, burn fat and to go through the pain barrier some will use amphetamines and opiates, either street preparations or illicit pharmaceutical supplies. In the UK the opioid nalbuphine (Nubain) has been abused in this way and, in cases where dependence becomes established, detoxification treatments can be necessary. 

By contrast, the stimulant amphetamines, such as D-amphetamine and methylamphetamine, release dopamine from most brain regions. These drugs also inhibit the reuptake of all biogenic amines, but the effects on the noradrenergic and serotonergic systems do not appear to be directly associated with the dependence potential of the drugs. 

There is no truth to these stories, but both MDA and MDMA can cause bad reactions at high doses. Some people snort them or (rarely) inject them intravenously, intensifying their action and potential for harm. Combining these drugs with alcohol or other depressants also increases the possibility of adverse effects. As sexual drugs, hoth compounds may enhance the pleasure of touching, but they interfere with erection in men and with orgasm in both men and w omen, A few cases of dependence on MDMA have been reported they resemble cases of amphetamine dependence. 

In an interview study (Robson and Bruce 1997), the dependence potential of various street drugs was assessed in 201 problem and 380 social users of heroin, cocaine or amphetamine using the well-validated Severity of Dependence Scale (SDS). Scores (maximum = 15) in the problem group were 12.9 for heroin, 9.6 for other opioids, 6.1 for amphetamine and 5.5 for crack cocaine. All of these scores were consistent with findings in other studies. Cannabis SDS score was 2.6 and comparable with those of LSD (3.1) and ecstasy (1.3), two drugs that are generally not associated with physical or psychological dependence. In the parallel sample of social users, the cannabis SDS was similar at 3.4. 

Schedule 11 drugs have an accepted medical use in the United States and a high rate of abuse, with either severe psychological or physical dependence potential. These drugs include morphine, codeine, cocaine, amphetamine, and most barbiturate preparations containing amobarbital, secobarbital, and pentobarbital. 

Despite public misconceptions, there is little firm evidence that the typical and atypical antidepressants produce dependence in clinical users. A review of 21 case reports of antidepressant addiction revealed that 12 were associated with tranylcypromine, although 8 of these 12 had a previous history of substance misuse (Haddad, 1999). Tranylcypromine s structural similarity to amphetamine may account for the significant number of reports of its addictive potential, but even here the term (mild) discontinuation reaction rather than withdrawal reaction should be used to allay any concerns patients might have (Haddad, 1999). 

Schedule II—The drug or other substance has (1) a high potential for abuse, (2) a currently accepted medical use in treatment in the United States or a currently accepted medical use with severe restrictions, and (3) abuse of the drug or other substances may lead to severe psychological or physical dependence. Examples cocaine, PCP, morphine, fentanyl and meperidine, codeine, amphetamine and methamphetamine, Ritalin . 

Ibogaine itself stimulates locomotor activity in rats. However, it reduces the locomotor activity induced by morphine, with greater effects in female animals than males (Pearl et al. 1997). It also reduces locomotor activity induced by cocaine and amphetamine (Sershen et al. 1992a, 1992b Blackburn and Szumlinski 1997). However, the interaction between ibogaine and cocaine is time-dependent, with motor activity inhibited at short delays, but potentiated at long delays (Maisonneuve et al. 1997). 

Amphetamines are powerful synthetic psychostimnlants with a high potential of addiction. They increase vigilance and the ability to concentrate, temporarily elevate mood, and stim-nlate motor activity. However, depending on the dosage and more importantly on the person s personality, they can cause various levels of euphoria, raise blood pressure, and facilitate contraction of the sphincter of the nrinary bladder as well as facilitate the development of mydriasis. 

Drug abuse and dependence These drugs are chemically and pharmacologically related to the amphetamines and have abuse potential. Intense psychological or physical dependence and severe social dysfunction may be associated with long-term therapy or abuse. If this occurs, gradually reduce the dosage to avoid withdrawal symptoms. 

Schedule II (c-/7) - High abuse potential with severe dependence liability (eg, narcotics, amphetamines, dronabinol, some barbiturates). 

Amphetamines and anorexic agents These drugs have potential for causing dependence, hypertension, angina, and myocardial infarction. High... 

Schedule II - The drugs at this level also have a high abuse potential and could cause psychic or physical dependence. They may be prescribed but are under stringent control. Schedule II drugs include opioids(morphine), amphetamines and methamphetamines used alone or in combination as well as some barbiturates. 

Schedule 3 involves drugs with a significant abuse potential, but lower than for Schedules 1 and 2. Such drugs may lead to moderate or low physical dependence or high psychological dependence. Examples include many stimulants such as amphetamines and methamphetamines as well as various barbiturates. Anabolic steroids (used by athletes and bodybuilders) are also included because of their serious health risks. 

Information on pemoline s tolerance and toxicity is not available. However, as with almost any drag, there is a chance of psychological and/or physical dependence with excessive doses and/or long-term misuse (57). In comparison to methylphenidate and amphetamine, pemoline has the least potential for abuse (39). Benowitz (41) suggests that approximately 3 mg/kg pemoline should be considered life-threatening. Treatment for overdose is similar to what has been recommended for methylphenidate and amphetamine. In cases of overdose, the administration of chlorpromazine has been found useful for decreasing the amount of CNS overstimulation (57). 

The treatment of narcolepsy with psychostimulants such as amphetamine 2 (Adderall), and methylphenidate 3 (Ritalin) has been reported.3 However, these are schedule 2 DEA-controlled substances and have a potential risk of abuse, overdose, and dependence, which present substantial barriers to widespread use.4 As a result, there has been a significant effort to identify novel therapeutic agents for the... 

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