OxyContin on the brain

With the removal of public funding for OxyContin this spring, some of Ontario’s addicted population will be experiencing neurological changes caused by drug withdrawal, according to Dr. Adam Newman from the Kingston Methadone clinic.

“Once you become addicted, your brain behaves in a very odd way. You lose the ability to control your need for that thing,” says Newman.

OxyContin is an opioid drug that acts on the reward center in the brain. The generic drug is called oxycodone.

The reward system works on different parts of the brain to induce pleasurable feelings and control behaviour.

The main reason opioids are used in medicine is to combat pain, says Newman. It does this by acting on the mu-receptors in the brain, blocking pain. When taken in high doses it acts like endorphins flooding the brain and creating a sense of euphoria similar to heroin.

Dr. Meldon Kahan is the medical director of addiction medicine at St. Joseph’s Health Centre in Toronto. According to Kahan, addiction is the inability to control your behaviour when seeking out a drug and while using it.

Yet, counter to what many people think, this inability to control behaviour is not simply a lack of willpower.

OxyContin changes the neurological structure of the brain, hijacking the reward center and making the user a slave to the drug, says Kahan.

All humans have a reward centre in their brain. It governs motivation and pleasure. It is also linked to our memory and our executive functioning. Humans experience dopamine spikes naturally and these help us survive as a species.

When we cuddle, have sex, eat or go for a run, endorphins are generated which cause dopamine to be released into our limbic pathways. Dopamine is a neurotransmitter that acts like the brain’s messenger.

Dopamine spikes cause a flurry of activity in the reward center, binding to neuro-receptors and telling our brain that we feel happy and at ease, says Kahan.

When endorphins are released, they are very fast-acting and quickly inactivated. When OxyContin is introduced to the nervous system, it has a much longer-lasting and potent effect.

The brain’s plasticity is partly what makes us able to learn and adapt. It’s ability to change is also what leads to drug addictions and terrible withdrawal symptoms when those drugs are taken away.

A brain constantly exposed to OxyContin is bombarded with pain-relieving and euphoria-inducing neurotransmitters. The brain adjusts to the overwhelming stimulation by reducing the number of receptors and decreasing their sensitivity to dopamine.

This reduction in the amount and sensitivity of neuro-receptors is what causes drug tolerance, says Kahan. The user then has to take more of the drug to feel the same effects.

“Addiction is like your brain at war,” says Kahan.

Part of your brain knows it’s bad for you, but the other part has a physical need for endorphins to function properly. Since the drug has decreased the amount and sensitivity of the receptors, your body constantly needs excessive amounts of endorphins and dopamine to function ‘normally’.

“If you take a lot of opiates, then you have fewer and fewer endorphins and your receptors are diminished, so when you stop the opiates, there is an endorphin deficit and the receptors are no longer working,” says Kahan.

“You feel terrible,” says Newman. “You feel acutely depressed and hopeless … like your whole body has been beaten.”

Newman says the main reason opioids are used in medicine is to combat pain. (repetitive) So when you suddenly take away the thing that has been relieving pain all over the body, you feel pain everywhere.

“Things go haywire,” says Kahan. “Endorphins help regulate a lot of things that are going on in our body. Withdrawal is an endorphin system that is not working properly.”

You get nauseated, sweat excessively, drool and sneeze. You have cramps and diarrhea because your bowels are no longer suppressed by the opioids.

To combat withdrawal symptoms, some doctors, like Newman, prescribe methadone treatment.

Methadone is an opioid like OxyContin, but it is highly regulated by the federal government. Taken at the appropriate dosage, it eliminates withdrawal symptoms and allows users to feel ‘normal’, says Newman.

Most OxyContin users that are prescribed methadone treatments go into the pharmacy every day and are given methadone mixed with juice under the supervision of a doctor or the pharmacist. Doctors have to seek special approval before being allowed to prescribe methadone.

Methadone is a longer lasting opioid that has a slow release in the body. This means it combats feelings of withdrawal for 24 hours, allowing the recovering addict to concentrate on school, work, or their families, says Kahan.

Some argue methadone treatment is just creating another addiction. Newman does not deny this argument.

“It’s a functional addiction,” he says.

For addicts who have felt and been treated like the scum of the earth, methadone treatment does wonders, says Newman.

“Suddenly they’re free. They don’t have to do crime or take dangerous impure substances. They’re being given a pure medical substance once a day, and they’re being given it by a professional who cares for them.”

Produced by Jordan Adams