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A Sneaky Drug

By Dr. Mohamed Izham Mohamed Ibrahim
The Sun, September 14, 1996

THE QUESTION THAT THE PUBLIC raises whenever a serious attempt is made to differentiate states of addiction or degrees of abuse probably stems from misconceptions concerning drug addiction. The misconception involves the naive belief that there is something magically drug-like about a drug, which makes a drug a drug.

Many substances are able to elicit a drug-like effect that is valued by the user. There is nothing intrinsic to the substances themselves that sets one active substance apart from another active substance; its attribute as a drug is impaired to it by use. One excellent example is caffeine and it is probably the most widely used of all mind-altering substance.

What is caffeine and caffeinism? The term caffeinism is used to describe the syndrome related to excessive caffeine use and preoccupation with this stimulant. Caffeine is a nitrogenous organic compound of the alkaloid group. Pure caffeine, 1, 3 ,7-trimethylxanthine (a chemical compound) occurs as a white powder or as silky needles, which melt at 238 degree C.

It is soluble in hot water and upon cooling, it deposits crystals of caffeine monohydrate. It is odourless but has a bitter taste. It was first extracted from plants in 1820. It is a substance that has marked physiological effects.

Caffeine can be found naturally in tea leaves (Thea sinensis), coffee beans (Coffea arabica), guarana, mate, kola nuts (kola acuminata) and cocoa beans (Theobrama cacao). In addition, caffeine is also found in over 60 plants and trees. One of these is quarana, a vine from the Amazon that belongs to the soapberry plant family.

Cofee is consumed either hot or cold by about one-third of the people in the world. Its popularity can be attributed to its invigorating effect, which is produced by caffeine. The best-known constituent of tea is caffeine, which gives the beverage its stimulating character. About 4% of the solids in fresh leaf is caffeine, and one teacup of the beverage contains 60 mg to 90 mg of caffeine.

Caffeine is present in ground coffee in amounts ranging between 0.75% and 1.5% by weight. The average cup of coffee thus contains about 100mg of caffeine.

The caffeine content of tea varies greatly, depending on the strength of the tea with an average of about 40 mg. There are also about 40 mg of caffeine in a glass of cola beverage (340 mg).

Caffeine content of beverages or preparations
Beverage or preparationCaffeine content (mg)Dose
Food & Drinks
Coffee, drip or percolated 100 - 50 one cup
Cofee, instant 50 - 70 one cup
Tea 30 - 90 one cup
Coffee, decaffeinated 1 - 6 one cup
Cola beverage 72 12 fluid ounces
Sunkist orange soda 42 12 fluid ounces
Milk chocolate 1 - 15 one ounces
Chocolate cake 20 - 30 one slice
Hot cocoa 5 one cup
Migraine drugs 100 mg/dose
Analgesic 15 - 40 mg
Cough/cold 15 - 125 mg/dose
Over-the-counter 65 - 250 mg/dose
Approximation based on range gathered from several sources

It is reported that Americans are consuming a daily dose of 500 mg to 600 mg daily and over 100 billion doses of caffeine yearly. That is roughly 5,000 tons (5,080,320 kg) every 12 months. Another studies indicates that 82% of the United States population drinks coffee and 52% tea, making coffee the most commonly used drug in America.

Forty-five per cent of the coffee drinkers consume three to seven or more cups daily. Add to this figures the consumption of caffeine in tea, cola drinks chocolate candy and hot chocolate and one begins to perceive the remendous consumption of the central nervous system stimulant.

In the soft drink market, the use of caffeine has now spread to orange drinks. But the mid-80s, decaffeinated coffee and soft drinks became widely available, giving consumers the choice of regulating their caffeine intake while continuing to enjoy these beverages.

What are the effects of this drug? After ingestion, caffeine quickly disperses throughout all organ systems, crossing both the blood-brain barrier and the placenta.

Studies have shown that caffeine has a stimulating effect on the central nervous system, heart, blood vessels and kidneys.

It also acts as a mild diuretic. Caffeine's potent stimulatory action makes it a valuabel antidote to respiratory depression induced by drug overdose such as morphine or barbiturates.

The positive effects that have been described in people who use caffeine include improved motor performance decreased fatigue, enhanced sensory activity and increased alertness.

The positive effects may partly explain the compulsion of many adults to consume coffee or other caffeine-containing beverages as part of the morning ritual of awakening.

However, caffeine intake may also produce in people such negative effects as irritability, nervousness or anxiety, restlessness, headaches and insomnia.

Caffeine is capable of exciting the brain at all levels, resulting in clearer thinking, greater sensitivity to stimuli, wakefulness, better physical coordination, including increased respiration.

It can also cause tremors or shakiness. In newborns, the metabolism of caffeine is markedly delayed, which contributes to caffeine toxicity in infants exposed to the substances.

Caffeine is clearly a drug and the habitual, excessive use of coffee and other caffeine-containing beverages is clearly drug dependence if not addiction. The same could be extended to cover tea or chocolates, if society whished to use and consider them that way.

The task of defining addiction then is the task of being able to distinguish between opium and chocolates while at the same time being able to embrace the fact that both can be subjected to abuse.

This requires a frame of reference that recognises that almost any substance can be considered a drug, that almost any drug is capable of abuse, that one kind of abuse may differ appreciably from another kind of abuse, and that the effect valued by the user will differ from one individual to the next for a particular drug, or from one drug to the next for a particular individual.

Clearly, caffeine is a potent drug in humans and is often toxic. Although the effects of caffeine toxicity are not completely clarified, there is more knowledge about its psychiatric manifestations. Some of these actions may predominate at different plasma levels of caffeine. The effects appear to be of little significance in smaller quantities.

However, it shows an important effect for patients with heart problems, ulcers, the very young and old, light sleepers and debilitated patients. The risk in morbidity increases by ingesting caffeine. Furthermore, it is believed that caffeine can be linked to birth defects such as cleft palates, heart abnormalities and missing fingers and toes of the foetus. Although caffeine is not as potent as nikethamide or strychnine, in large amounts it can be just as toxic.

Tolerance to the effects of caffeine can develop. No doubt some people have become addicted to ir or become psychologically dependent on their favourite caffeine drink.

In caffeinism, headache, delirium, agitation, anxiety and heart palpitations are typical. An abrupt end to taking caffeine in the heavy user may lead to the following relativelt mild withdrawal symptoms: restlessness, irritability, headaches, shakiness, inablity to work effectively and lethargy.

Actions of caffeine in the body
Body PartsAction
Brain Clearer thinking, greater sensitivity to stimuli, wakefullness, better physical coordination, incrased respiration, tremors/shakiness, convulsion, death
Cardiovascular Irregular heartbeat, small rise in overall blood pressure
Bronchial tubes dilated
Stomach and gastrointestinal tract gastric irritation; increased secretion of digestive juices
Muscles increased capacity for work
Basal metabolic rate (BMR) slightly increased
Embryo there is evidence that caffeine is possibly teratogenic to the embryo in the first trimester of pregnancy
Urinary tract diuresis

How much caffeine have we consumed? Let us ponder. If your child started drinking cola beverages at the age of eight and looking forward to 60 or more years of drinking cola beverages of one regular 12-ounce (340 mg) cola evert other day, with their contents of sugar, acid, caffeine and empty calories, he can look forward to having consumed 770 mg (1.7 poinds) of caffeine, aquarter ton of sugar and enough acid to have dissolve his teeth many times over.

Caffeine is widely available in both beverages and medications. The recent news in the New Straits Times(Sept 4, 1996) discussed the area of sports medicine, which brought up the issue of drinking coffee and tea among the athletes. The concern was on the risk of being banned for doping

Various concentrations of caffeine are also detected in the "ecstasy" pills, which range from 1mg per pill.

We need ot start reducing and controlling excess caffeine in our daily diet. Health professionals and organisations need to educate the public and carry out an anti-caffeine campaign, especially aimed at pregnant women.

The purpose is to urge them to avoid beverages or preparations which contain caffeine during pregnancy or gestation. More studies need to be conducted nationwide to research the effects of caffeine among the Malaysian society. If the negative effects of caffeine are significant, there must be rules for labelling all caffeine-containing products, especially for pregnant women or nursing mothers, to warn them not to use the product. One doesn't know one is addicted until one stops using it.

The writer is a pharmacist, an associate at the National Poison Centre and a lecturer in Social Pharmacy at the School of Pharmaceutical Sciences, USM.

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