Tremor cocaine-induced

The elation and euphoria that cocaine induces in susceptible individuals tend to render it a habit drug, but it is more apt to be used for occasional jags, by criminals, rather than daily, as is morphine. The treatment is therefore easier and more likely to be successful. However, it may be used continuously as it was by the South American natives in India, it is combined with the chewing of betel leaf. Cocaine inebriation is active and sociable, in contrast to the dreamy state induced by morphine. It may also induce a more or less maniacal condition, in which the individual becomes dangerous to others. The immediate effects include the phenomena of sympathetic stimulation, resembling hyperthyroidism tachycardia, polypnea, mydriasis, exophthalmos, and fine tremors. Some individuals, especially women, react with marked erotic excitement. The stimulation is succeeded by depression, tremors, pallor, and sunken and unsteady eyes. 

Animals self-administer cathinone in a pattern common to abuses of monoamine stimulants such as cocaine (Woolverton and Johanson 1984). Cathinone can induce a conditioned place preference in rats (Schechter 1991). Withdrawal symptoms of khat include lethargy, depression, nightmares, and mild tremor (Kalix 1994). /V-methylated cathinone (methcathinone) is more potent, and has become available on the illegal market. It was subsequently scheduled as a controlled substance (Glennon et al. 1995). 

Recall from our discussion of cocaine and amphetamines that the body responds to the long-term abuse of these stimulants by creating more depressant receptor sites. Likewise, the body recognizes the excessive inhibitory actions produced by alcohol and tries to recover by increasing the number of synaptic receptor sites that lead to nerve excitation. A tolerance for alcohol therefore develops. To receive the same inhibitory effect, the drinker is forced to drink more, which induces the body to create even more excitable synaptic receptor sites. Eventually, an excess of these excitatory receptor sites leads to perpetual body tremors, which can be subdued either by more drinking or, with greater difficulty, by a long-term cessation of alcohol consumption. 

At higher doses, cocaine can produce undesirable effects, including tremor, emotional lability, restlessness, irritability, paranoia, panic, and repetitive stereotyped behavior. At even higher doses, it can induce intense anxiety, paranoia, and hallucinations, along with hypertension, tachycardia, ventricular irritability, hyperthermia, and respiratory depression. In overdose, cocaine can cause acute heart failure, stroke, and seizures. Acute intoxication with cocaine produces these various clinical effects, depending on the dose these effects are mediated by inhibition of the dopamine transporter and in turn by the effects of excessive dopamine activity in dopamine synapses, as well as by norepinephrine and serotonin in their respective synapses. 

Central nervous system toxicity is rarely observed with catecholamines or drugs such as phenylephrine. In moderate doses, amphetamines commonly cause restlessness, tremor, insomnia, and anxiety in high doses, a paranoid state may be induced. Cocaine may precipitate convulsions, cerebral hemorrhage, arrhythmias, or myocardial infarction. Therapy is discussed in Chapter 59 Management of the Poisoned Patient. 

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