lately, thanks to Toronto Mayor Rob Ford - what exactly is crack-cocaine? Is it really as

'whack' as it's portrayed to be?

Crack is simply another form of cocaine, which comes from the leaves of a coca plant. After

mixing powdered cocaine with a weak base, such as baking soda, it changes composition

and a solid is produced, often referred to as 'rocks'. This solid has a much lower melting

point than cocaine (90C vs 190C) allowing it to be smoked, as opposed to snorted. In

fact, it's called 'crack' because of the sound it makes when heated. But why smoke it? Well,

the lungs are an extremely quick and effective way of getting something into the bloodstream.

Those with asthma, for example, use inhalers to quickly put a drug directly into their

system. When smoke meets the large surface area in your lungs, it too slips right through

the membrane, and heads straight to your brain, in as little as 8 seconds. This is much faster

and more intense than the effects of snorted cocaine which generally takes around 10 minutes

to reach the brain.

However, once in the brain, crack and cocaine are effectively identical. Initially, users

feel energized, alert and much more aware of their senses. In the brain, crack acts

on the Ventral Tegmental Area, releasing large amounts of dopamine - the chemical often associated

with feelings of pleasure and euphoria. This dopamine travels between brain cells - called

neurons - and binds to receptors that trigger the good feelings. Now, normally, this dopamine

would be reabsorbed back into the neuron by a dopamine transporter; however, crack alters

this process. It attaches to the transporter, and blocks the reabsorption, allowing dopamine

to build up and continually stimulate the receptors. As a result, you feel - well - really

good for around 10 minutes.

But soon after, the dopamine levels in the brain plummet, causing an extreme low and

often feelings of depression. Which is why many users typically smoke more, hoping to

reach that high again. Unfortunately, these dopamine levels can take a long time to naturally

replenish, contributing to physical and psychological dependence or addiction, as well as increased

irritability, restlessness and paranoia.

In some cases, crack or cocaine abuse can lead to something called Delusional Parasitosis

- the feeling that bugs or insects are crawling under the skin. This often leads to self-destructive

behaviour, like scratching or biting, in an effort to get rid of the imagined bugs. In

the most serious cases, crack's impact on the heart can cause heart attacks, strokes,

or even stop the heart altogether, leading to death.

Simply put, on the extreme end of things, crack can get pretty whack!

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