Examining Drugs Of Abuse Biology Essay

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It is also known as substance abuse. Most professional define it as the use of illegal drugs. It is the harmful use of any drug or substance for mood altering purposes. Medically, It is the use of illicit drugs for purposes other than those for which they are indicated. There are substances that can be abused for their mood altering effects that are not drugs at all such as inhalant and solvents and there are drugs that can be abused that have no intoxication purposes such as anabolic steroids.

People who smoke marijuana argue that it is not addictive and it has so many beneficial qualities unlike other so called harder drugs. But recent research shows that it has more harmful physical, mental and psychomotor effects. Almost any substance can be abused. Illegal drugs are not the only substances that can be abused, alcohol, prescription, inhalants and solvents and even coffee and cigarettes can all be abused.

History of Drugs of Abuse

Drug use and abuse is as old as mankind, it dates back as far as 2737BC. You notice when you use something quite often, you get used to it and you mal-use it and abuse it. Humans have used drugs of one sort or the other for thousands of years as we have always had the desire to eat or drink substances that make us feel relaxed and stimulated.

Home remedies

This was discovered to alleviate aches, pains and other ailments and most of the preparations were herbs, roots, mushrooms and fungi. They had to be eaten, drunk, rubbed on the skin or inhaled to achieve the desire effect.

Religious rites

Some of these preparations were discovered to produce exaltation and trance like states. Drugs were used to see visions or gain insights, dull the pain of ritual mutilation in initiation ceremonies, to enhance the strength and pain resistance of warriors to prepare them for battle, to relax during celebrations.


The UK Home Office estimated that the social and economic cost of drug abuse to the UK economy in terms of crime, sickness is in excess of £20 billion a year.

What causes drug abuse?

The causes depend on the nature of drug being used, the person taking the drug and the reason and circumstances under which it is taken.

Some medications such as painkillers or sleeping pills are physically addictive. They have an effect on the body, which leads to tolerance and withdrawal symptoms, while others may lead to a psychological addiction if people have a craving for the effect that the drug causes.

Social circumstances are important in drug abuse. Peer pressure, emotional distress; ease of access to drug and low self-esteem can all lead people to drug abuse.

Warning signs of drug abuse

*Expressing feelings of depression

*Making inappropriate remarks

*Inability to relax

*Frequently selling possessions, borrowing money or stealing from someone.

Basic facts about drug abuse

*It can be physical, psychological or both.

*Takes over the user's life

*Disrupts a person's relationship and daily functioning

How it is used

A drug is any substance that when absorbed into the body of a living organism, altars normal body functions. We cannot predict the effect of a drug on a human body especially if it is taken for the first time even the dose is of very small amount. The brain and body chemistry of everyone is unique and everyone's tolerance for any drug is different. Since every drug has various effects on a living organism, it can be good or bad. Drugs that are legal (prescription and OTC medications) can also become dangerous as illegal drugs. Use of drugs can become abuse; it can lead to addiction, serious health problems and even death.

Drug abuse

Drug abuse is potential and known adverse effects linked to improper use, such as psychiatric medications with sedative, analgesic, or stimulant properties. Drinking an occasional glass of wine is considered acceptable in many Western countries, while drinking several bottles is seen as an abuse.

Drugs of abuse are: Alcohols, heroin, anabolic steroids, inhalants, cocaine, marijuana, dissociative drugs, MDMA, GHB and Rohypnol, hallucinogens, nicotine, methamphetamine, club drugs, prescription medications, tobacco addictions.


There are five primary types of drug testing that is urine, blood, hair, saliva, and sweat.

Urine Drug Tests

Drug testing through urine is the most common among all types. It is considered as an intrusive method of drug testing. It is the least expensive method ranging $7 to $50. This test detects the presence or absence of drug metabolites, remaining of drug that retains in the body for certain time period after the drug effect have worn off. This can be easily done at home. Urine tests results can be affected by abstaining from drug use for a period of time before the test. This affects the reliability of urine test.

Saliva Drug Tests

Saliva drug tests are a little more expensive than urine testing, but less than hair or blood. It ranges from ranging from $15 to $75 per test. Saliva tests are considered a relatively nonintrusive method of drug testing. Saliva test detects drug abuse for shorter periods of time (within 24 hours). As accuracy goes, saliva tests are more reliable for detection of Methamphetamine and Opiates, less reliable for THC.

Hair Drug Tests

It is nonintrusive method of drug testing. This type of testing is very much expansive then urine and saliva tests. It ranges from ranging from $100 to $150 per test hair follicle tests detect substance use for longer time (up to 90 days, depending upon hair length), but do not usually detect use within the past week. This test detects the use of opiates (codeine, heroin) very easily. For positive test more than 1 strand of hair is required approximately the diameter of pencil and each strand of 1.5 inch long. Hair drug tests now check for SAMHSA-5, and include at least Cannabis, Ecstasy/MDMA, Cocaine, Opiates, Methamphetamine, Amphetamine, Phencyclidine (PCP), Benzodiazepines, & Barbiturates.

Blood Drug Tests

Blood drug testing is the most expensive method among all.  It is considered the most intrusive and accurate method. It measures the actual amount of drug in blood especially alcohols.

Sweat (Patch) Drug Tests:

weat drug tests are considered a relatively intrusive method of drug testing because they require the wearing of a patch for an extended period of time. The chances of contamination are very much high which may end up in false reading. This test is not very accurate. The sweat patch is still relatively uncommon.


Detection times in urine are significantly greater than detection times in blood, but do not provide information as to whether the individual is under the influence at a particular time.

Urine specimen can be adulterated, substituted, or diluted.

Biological hazards may be introduced to the specimen through handling and shipping to the lab.

In some cases the laboratory will only report the result of a drug ordered for testing.

Oral fluid (saliva)-

A drug and its metabolites do not remain in oral fluids as long as they do in urine. Approximately 10-24 hours.

Detection periods are normally half or less than that of urine. E.g. Amphetamines- 2-48 hours in saliva,1-4 days in urine. Cannabinoids (THC-Marijuana)- 1-18 hours in saliva, 30+ days in urine.

Less efficient way of testing.

May not detect drugs that other methods would, leading to wrongful acquittal.


Detection depends on the length of hair in a sample.

THC does not readily deposit inside epithelial cells so amount of testable traces can be adulterated by cosmetics.

Drugs consumed recently before a test cannot be detected.

Takes a week for drugs consumed to be reflected in hair test results.

Drug user may resort to shaving their hair to avoid detection.

Spray (sweat) patch test-

A limited number of labs in the UK are able to process results.

A patch can retain evidence of drug use up to 7 days.

Low levels can be detected 2-5 hours after use.

The rate of sweat production is variable between possible donors.

Limited to the number of drugs it can detect.

Post in vivo sampling and the laboratory methods used for detection

Mass spectrometry

High performance liquid chromatography

Gas chromatography

Mass spectrometry

An unknown Compound is inserted into the mass spec and vaporised the product is then ionized by way of an electron beam. The resultant Electromagnetic charge organises the Ions by electron mass which are separated out by their mass to charge ratio. The Ions are then detected quantatively. The Ions are then identified give and the mass spectra is determined.

High performance liquid chromatography

A small portion of the Compound for test is mixed with a solvent and drawn into a syringe. The sample is then added to the heater injector port of the GC, the mixture and the carrier gas are both volatilised and will emerge as a chromatograph at a specific time, i.e. the retention time. The time it takes to emerge as a vapour is specific to the compound under test and the retention time is compared to a reference sample giving a definitive result.

Gas chromatography

This process uses two phases of the compound under test, the mobile and stationary phases. The mobile phase is a solvent or solvent mix and the stationary phase is generally the solid coated around glass beads. The molecules which have a preference for the solid phase will separate out less speedily than the mobile phase molecules, this process allows the Selective partitioning of the molecules of interest. The variation in separation times allows for component detection and compound verification.

Limitations of drugs used as evidence

Although drugs test results can be of great advantage to both prosecutors and defense in legal proceedings, there are limitations that may inhibit the reliability of the information derived. A constraint of this type of evidence may be that there is not enough space and time attributed to the discussion of scientific and technical aspects of drug-use testing. A jury in a case may only be provided with conclusive evidence such as positive or negative results, and are neglected of possible sources of error. Technical errors such as false-negatives or false-positives can occur as a result of misidentification of a drug. Because of this, evidence may become unreliable and so it gives allowances for misjudgments to be made.

Incorrect quantification of a drug detected in a donor specimen is a problem that can occur but is not easily discoverable. This is due to the high frequency of drug-use tests done in laboratories. Even if these errors are found, the companies conducting these tests are reluctant to disclose this information as it may affect future work. The effect of quantification errors has led to laboratory testing organizations establishing tolerances. And so they are required to adhere to established cut-off concentrations. This means that a certain amount of a drug can be present in a donor sample and be recorded as "negative".

Although tests for drug use can be specific to an extent, results of a test do not determine whether a donor was impaired by the drug in question, or was unfit to carry out normal responsibilities at the time of a test. Also, the dose of a drug or the form it was taken in cannot be established by the positive result of a single test or test method.

Celebrities Died From Prescription Drug/ Drug Abuse

There are a lot of celebrities who have died from prescription drug/drug abuse. More than half of these celebrities died accidently but later it was found out that their body contains drug metabolites of several drugs. Some of them are:



Michael Jackson

Propofol (anesthetic), Xanax (anxiety), Dilaudid (painkiller), Valium (anxiety), Ambien (sleep), Fentanyl and Vicodin (painkiller).


Cocaine, Oxycodone and Vicodin (painkillers), Ativan, Xanax and Klonopin (anxiety), Benadryl and Levamisole (a drug used to cut Cocaine)

Corey Haim

Soma (muscle relaxer), Valium (anxiety), Vicodin (painkiller)

Marilyn Monroe

barbital (AKA Nembutal) and chloral hydrate (sleeping pills)

Dorothy Dandridge

Imipramine, AKA Tofranil (antidepressant)

Bruce Lee

Equagesic (painkiller)

Freddie Prinze

Methaqualone, AKA Quaaludes (sedative)

Dana Plato

Carisoprodol, AKA Soma (muscle relaxant), and Vicodin (painkiller)

Gerald Levert

painkillers Vicodin, Percocet and Dextropropoxyphene (AKA Darvocet), sedative/anxiety medication alprazolam (AKA Xanax) and two non-prescription antihistamines

John Belushi

Heroin and cocaine overdose

Janis Joplin

Heroin overdose

Case studies in law

Bass V. Florida Department of law enforcement.

The plaintiff, a corrections officer had appealed that justice certification be revoked based on a positive urine analysis and that hair analysis be used as a reinforcing measure toward the conviction of Bass. Urine analysis is not solid enough to secure a conviction and both analyses in tandem should be used to rule out a false positive. On remand, the hearing officer disregarded the hair analysis along with the urine analysis results. The lower court from which the initial demand the analysis ruled that either test is admissible in court and can lead to conviction based on the subsequent results.

Custody hearing - pending Livonia michigan, 1998

Concerned by his ex wife's behavior whilst with child, the estranged husband of the woman, whom had contact rights, sought the scientific opinion of an investigator. The mother was, on several occasions, seen to be smoking cannabis and the smell was apparent when handing the child to the father. A hair sample was taken from the child and a toxic screening carried out. The case was sensitive as it was not intended to prove inhalation of the drug by the child but merely to reinforce a custody case. The hair was washed externally of contaminants and prepared for toxicological analysis. The hair did indeed prove positive for for THC (the active constituent of cannabis).

Angel V Chief constable of south Yorkshire [ 2010] EWHC 883 (Admin) (23 March 2010)

The appellant was arrested after being suspected of driving under the influence of drugs. The appellant refused to give a blood sample and was subsequently charged with failing to give a sample without reasonable excuse. The appellant admitted smoking cannabis and a roadside impairment test enforced this admission. After arrest and custody the police conducted a alcohol breathalyzer test which proved negative. The Police surgeon, after examination of the appellant concluded that the intoxicative behavior of the appellant may indeed have been due to the ingestion of a Class B compound based on the physiological examination.