Drug addiction, substance abuse and the role of dopamine

Cocaine and caffeine

Both are a powerful stimulant which increases dopamine levels and can be habit-forming. They increase mood, alleviate boredom and fatigue and caffeine increases the effects of alcohol.

Cocaine causes a distinct euphoria than other addictive drugs, and behavioral studies in rats with cocaine experience have shown that they know the good effects of the drug as well as the bad side effects. They are able to locate places where they got immediate cocaine injections which gave them instant satisfaction but avoided places where they were moved 15 minutes after the cocaine had won off because by that time, they would be experiencing bad side effects.


Methamphetamines and amphetamine related substances are stimulants that increase dopamine levels by maintaining rapid increase of dopamine. Some foods like cheese, chocolate and sausage may contain amphetamine like substances which are in the same group to methamphetamines which can be used to make a drug known by the street name as ‘Ecstasy’.


These include morphine, heroine, fentanyl, codeine and oxycodone. These indirectly cause elevation of dopamine and produce a euphoric effect unique from that of cocaine and amphetamines because they act on different parts of the brain.


Alcohol is a depressant at high doses and a stimulant at low doses. At low doses, it elevates brain dopamine levels and can be habit forming. The mechanism by which alcohol increases dopamine is not clearly understood because unlike other addictive drugs, alcohol does not have a specific part of the brain where it acts. This is why even though the taste of alcohol may be unpleasant to new users, experienced users have a persistent craving because they are guaranteed of the feeling that comes after taking alcohol.


The euphoria of cannabis is distinct from other drugs as it acts on different places in the brain to elevate dopamine levels. Most pot enthusiasts and self-proclaimed cannabis connoisseurs have manipulated oral consumption of marijuana into edibles (cakes, brownies) but these have a risk of overdose.

It must be clearly understood that the hormone dopamine is central in addiction and any substance or activity that increases its levels has the potential for addiction. However, the continuous use of these substances leads to loss of sensitivity in users, thus the individual will require much higher doses to achieve the same pleasure and this can unfortunately lead to an overdose and subsequently death.

This article was contributed by Jonathan Kaundula, a UK based pharmacist. Send comment to: phirimclaw@gmail.com.

Leave a Reply

Your email address will not be published. Required fields are marked *