Narcotic

The detection of narcotics and other drugs of abuse in the blood, body fluids, and tissues of drug abusers and corpses where the suspected cause of death is related to drug overdose is routine procedure in forensic laboratories. The National Institute on Drug Abuse (NIDA), the Federal Bureau of Investigation (FBI), the Drug Enforcement Administration (DEA), and the Department of Justice are the agencies responsible for drug research and preventive programs, regulatory control, classification of drugs of abuse, and law enforcement.

Narcotics are opium (a substance naturally occurring in poppy seeds) and semi-synthetic opioid substances used to relieve intense pain. These drugs block specific receptors that processes pain information in the central nervous system (CNS), such as the brainstem, medial thalamus, spinal cord, hypothalamus, and limbic system, along with peripheral nerve fibers. Narcotics are addictive substances due to the euphoric effect they have on mood and general disposition. Morphine, codeine, and heroin are the main drugs of abuse in the narcotic category.

Morphine is a controlled medication prescribed for the treatment of intense chronic pain and for post-surgery pain due to its strong analgesic (pain-relieving) properties. However, morphine is highly addictive and can present dangerous side effects. Ordinary doses of morphine may lead to respiratory depression, or the slowing or cessation of breathing, through the reduction of sensitivity of the brain cells that regulate breathing. A study funded by the National Institute on Drug Abuse has shown that the chronic administration of morphine to rats reduced the size of nerve cells that produce dopamine by 25%. Dopamine is a natural brain chemical messenger (neurotransmitter) that causes sensations of pleasure, joy, and reward. The euphoric effects of morphine and other opiates indicate that they act upon the dopamine receptors. It is also known that cells decrease sensitivity to a given medication when frequently exposed to it. Therefore, such observed cell size reductions may be the result of cell desensitization to the drug. This explains the tolerance effect that morphine and other drugs of abuse cause in the CNS, leading addicts to intake increased doses to obtain the same initial effects of euphoria. It also explains the deep depressive episodes that take place when the effect of the drug ceases, or when abusers are under detoxification treatment. Besides addiction, the other side effects of morphine chronic intake are sedation, constipation, nausea and vomiting, urinary retention, and respiratory depression. Withdrawal causes acute depression, tremors, emotional instability, and irritability.

Heroin is an illegal and highly addictive narcotic with the fastest action on brain receptors. Heroin is a semi-synthetic derivate of morphine, sold on the black market either as a black gluey substance known as "black tar" or in a more "purified" form, mixed with sugar, starch, powdered milk, or quinine. The purification process is done by reacting heroin with other drugs or poisons, such as strychnine, which increases the risk of death or irreversible brain damage. Since abusers usually inject heroin in an intravenous or intramuscular solution, often while sharing needles, the risk for abusers contracting hepatitis C and HIV is a large concern among public health authorities. Other forms of heroin consumption involve inhaling it through the nose (snorting) or smoking the drug. As tolerance develops, abusers may inject heroin three or four times per day. After the initial rush of euphoria, users become drowsy, respiratory depression sets in, and higher mental functions are clouded. Heroin is converted into morphine in the brain, so the withdrawal symptoms are the same as with morphine, although more severe with heroin. Another risk imposed by heroin is that its illegal manufacture is accomplished by criminals who use toxic compounds and poisons in the process. The product can also be mixed with other dangerous drugs. In addition, the user does not know exactly how much heroin is in the purchased drug; it may have enough to induce an accidental overdose. It can also be contaminated with fungus and other pathogens, leading to infections. Lung complications, such as tuberculosis and pneumonia, are common among drug abusers. Inflamed veins or arteries are also common, due to the poor solubility (dissolvability) of substances mixed with the abused drugs.

Law enforcement against international drug traffickers who illegally bring narcotics and other illicit drugs of abuse into the United States requires a continuous effort and strategic planning from the FBI and DEA. It also involves collaboration with other international agencies, such as Interpol and the police of other countries where these drugs are originally produced, as well as those that are used as routes for drug dealers.

Forensic identification of addicts involves the examination of physical indicators such as needle marks in the veins of arms and legs, bluish bruises due to collapsed veins in these areas, and pinpoint pupils. Frequent snorting of cocaine or heroin leads to the destruction of nasal cartilages and nosebleeds. To determine what drugs a suspect is using, laboratory tests are performed on blood or urine samples that allow for the detection of both classes of drugs and specific drugs of abuse. Interrogation of arrested addicts helps local investigators to identify and arrest street drug dealers. The use of trained dogs in ports and airports is also a useful resource for the rapid identification of packages and luggage containing drugs. In the past, "mules," or people hired to carry drugs between countries, hid drugs wrapped in plastic inside their own body cavities. After the installation of x-ray scanners in airports, mules were more easily detected and arrested.