Drug and Drug Abuse

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Drug and Drug Abuse

Introduction

A drug is a chemical substance made of structures, apart from a nutrient or an important dietary constituent, which, when given to an organism generates a biological effect. Drugs are mostly used for medical purposes, but, they may have an adverse to the living organism. Some are used for non-medical purposes include drugs of abuse, drugs used to enhance athletic performance, and those taken for cosmetic purposes or for purely social reasons. Some drugs are used in the aspiration satisfaction or a non-health related aim. The paper talks about drugs and drug abuse.

However, repetitive exposure induces widespread adaptive changes in the brain, as a consequence drug may become compulsive-the hallmark of addiction. Current research has led to the understanding and differentiation of addiction and dependence. The former term physical dependence is currently known as dependence, while psychological dependence is simply termed addiction. Addictive drug has its own effects, but euphoria and reward feelings are shared by all drugs. With repetitive exposure, addictive drugs induce adaptive changes such as tolerance that is the escalation of dose to maintain effect. Once the abused drug is no longer available, signs of withdrawal become obvious. Withdrawal syndrome is the term given to the combination of these signs and they define dependence.

Dependence is not often a correlate of drugs as it can as well with various nonpsychoactive drugs classes for example bronchodilators, sympathomimetic vasoconstrictors and organic nitrate vasodilators. Addiction on the other hand, consists of compulsive, relapsing drugs used despite negative consequences, at times triggered by cravings that occur in response to contextual cues showed in the (experiment done on animal models mostly rodents which will learn a behavior for example press a lever when paired with drug administration). While dependence will invariably occur with chronic exposure, some organisms will develop a habit, lose control, and become addicted. Only one person out of six will become addicted within 10 years of first use of cocaine. On the contrary, relapse is common in addicts following effectual withdrawal and they no longer become dependent.

To comprehend the lasting effects induced by drugs and drugs of abuse, their original molecular, and cellular targets should be recognized. The target site of addictive drugs is usually the Mesolimbic dopamine system. The system begins from the ventral tegmental area (VTA), a minute structure at the brainstem’s tip that directs to the nucleus accumbens, the amygdala, and the prefrontal cortex. Robinson & Berridge (2003) says, “Most projection neurons of the VTA are dopamine-producing neurons and that when the dopamine neurons of the VTA begin to fire in bursts, large quantities of dopamine are released in the nucleus accumbens and prefrontal cortex” (pp 205). Direct drugs application into the VTA also act as reinforcers, and direct drug administration of drug of abuse results to the release of dopamine. Examples of drugs abused include minoxidilpx for baldness, sildenafil for erectile dysfunction, oral contraceptives, nicotine, cocaine, ecstasy, cannabis, alcohol, benzodiazepines, and inhalants amongst others.

In conclusion, society in general disapproves of drug abuse, because in most cases there is a social cost, damage quality of life, for example, mental incapacity and liver damages, over dosage, high risk of HIV infection.

References

Goldman, D., Oroszi, G. & Ducci, F. (2005). The genetics of addictions: Uncovering the genes.

New York. Nat Rev Genet Publishers.

Robinson, T., & Berridge, K. (2003). Addiction. Washington DC. Annu Rev Psychol Publishers.