Addicted to coffee? You may not be very far from those addicted to cocaine.
Need that cup of coffee before you finish your morning business? Can’t do without the smoke after that satisfying meal? Need a drink to fall asleep after a tiring day at work?
Welcome to the world of addictions.
The dictionary defines 'addiction' as a condition of being physically and mentally dependent on a particular substance. These are many and varied. While some medical practitioners believe that the potential for a drug to be addictive can be judged in terms of the harm it causes, others pin it on the ease of availability and the street value of the drug. Some research indicates the extent to which the drug activates the brain's dopamine system, and others evaluate addiction based on how pleasurable the drug is reported to be, the degree to which it causes withdrawal symptoms and how easily a person will become hooked to the drug.
However, there are also other facets to measuring the addictive potential of a drug, says Eric Bowman, lecturer in psychology and neuroscience at the University of St. Andrews in his column in CNN. In 2007, researchers from varied schools of thought came together as a panel to rank drugs based on addictiveness. The team was led by Professor David Nutt, the director of the Neuropsychopharmacology Unit in the Imperial College.
Here are the top five drugs they found most addictive in the order of most to least. While other research found the order of addiction slightly different, the drugs remained more or less the same.
1.) Heroin
This particular team ranked heroin as the most addictive drug based on the level of dopamine in the brain's reward system increasing by up to 200 per cent on the animals experimented on in the lab. In addition, the dose of heroin that can cause death is only five times greater than the dose required for a high. You want to be high, but do you want to die?
2.) Cocaine
Cocaine is derived from the coca plant that grows natively in South America. It is illicitly manufactured in either a white powder or rock form (‘crack’). While it ranks second on this list, the American Addiction Center ranks it to be the most addictive substance. It directly interferes with the brain's use of dopamine to convey messages from one neuron to another, preventing neurons from turning the dopamine signal off. This results in abnormal activation of the brain's reward pathways. In experiments, the team found that cocaine caused dopamine levels to increase more than three times the normal level.
It is estimated that between 14 million and 20 million people worldwide use cocaine and in 2009, the cocaine market was worth about $75 billion. About 21 per cent of people who try cocaine become dependent on it.
3.) Nicotine
Nicotine is the main addictive ingredient of tobacco.
When somebody smokes a cigarette, nicotine is rapidly absorbed by the lungs and delivered to the brain. While the panel rated nicotine (tobacco) as the third most addictive substance, there are researchers who rank it the second most addictive substance, next only to cocaine. According to the 2014 Surgeon General’s Report (SGR), nearly 90 per cent adult smokers started before age 18. Almost all started by age 26.
The report estimates that about 75 per cent high school smokers became adult smokers — even if they intend to quit in a few years.
According to a 2017 WHO report on the global tobacco epidemic, there were more than 1 billion smokers globally — as much the population of India.
Interestingly, during experiments, it was found that laboratory animals had the good sense not to smoke. However, rats pressed a button to receive nicotine directly into their bloodstream — this caused dopamine levels in the brain's reward system to increase anywhere between 25 to 40 per cent.
4.) Barbiturates
Also known as 'downers', barbiturates are a class of drugs that were initially used to treat anxiety and to induce sleep.
It goes by a variety of monikers, so don’t get fooled when someone offers you 'blue bullets' or 'gorillas' or 'nembies' or 'barbs' or 'pink ladies'. At low doses, these are known to cause euphoria, but at higher doses, these can be lethal because they suppress breathing. Barbiturate dependence was common when the drugs were easily available by prescription but declined dramatically since other drugs started replacing them. Cleary, availability is a huge factor in addiction — if a drug is not widely available, it ceases to be a potential addictive.
5.) Alcohol
Known to increase the dopamine levels in the brain anywhere between 40 to 360 per cent, some researchers claim that alcohol is more harmful than heroin or crack. In fact, according to an article in The Economist, alcohol is the most harmful drug in Britain — far more damaging than heroin or crack cocaine.
Reportedly, around 22 per cent of the people who have taken a drink will develop a dependence on alcohol at some point during their life.
The WHO has estimated that 2 billion people used alcohol in 2002 and more than 3 million people died in 2012 due to damage to the body caused by drinking.
Other drugs that featured in the research papers included methamphetamine (crystal meth), MDMA (also known as ecstasy or Molly), amphetamines, CNS depressants (Valium, clonazepam, z-drugs), and even caffeine (beware of that cuppa!)
So the next time you feel you cannot do without a certain drink, medicine or a snack, make sure you check the ingredients for the above-mentioned compounds.
You could be addicted without even realising that you are.