[parkovski]

There is. Cocaine and most other hard stimulants cause lots of dopamine to be released in the brain. Generally when you have higher concentrations of a neurotransmitter than normal for a long time, your brain compensates for the overstimulation by reducing the number of receptors. It doesn't work in exactly the same way as this drug but the end result is the same - reduced number of dopamine neurons, which causes parkinson's symptoms.

The scary thing about this drug is that it doesn't really have anything to do with the fact that they were trying to make opiates, it just happens that if you mess up the reaction you get this really toxic byproduct. As governments keep banning new drugs, chemists (amateur and professional, but it's hard to know which is which since this is all unregulated) keep coming up with new not technically illegal ways to achieve the same effects, and it's really just a matter of time before you create something else toxic. And it's entirely possible that some designer drugs that seem safe at first can end up having bad complications later on, since they're not very well researched and understood. At least we know how toxic meth is - with research drugs, especially newly discovered ones, no one really knows what kind of damage they're doing to themselves.

[etrautmann]

Careful there - the compensatory decrease in number of receptors is NOT the same thing as a reduction in the number of neurons. Each neuron will have a lower response to the same amount of dopamine, but the neurons will still be there and will be healthy.

In Parkinson's, a specific group of neurons in the Substantia Nigra (which do happen to be dopaminergic neurons), selectively die off. They no longer release dopamine to their downstream targets, causing the motor and other affects characteristic of PD.

The compensatory mechanism you described is unlikely to cause those specific neurons to die, unless something far more complicated is going on, which you can almost never rule out but doesn't tell us much.

edit for clarity

[Retric]

causes parkinson's symptoms != causes Parkinson's.

However, if you combine fewer neurons and fewer receptors there is presumably going to be a faster apparent disease progression.

[droopyEyelids]

This gets really scary when you realize it's not just chemicals that we recognize as drugs that can have these effects- it's every chemical developed by every industry in every product we're exposed to in the world.

In a way it's nice and calming to think, "oh, if I don't abuse illegal drugs I'm not affected by this. Most non drug chemicals don't cross the blood brain barrier anyway"

But then you might remember the NYT's attempt to do an expose on drinking water. http://www.nytimes.com/2009/12/17/us/17water.html

Chemicals that the EPA tests for stop being produced, industrial chemist tinker with them in the exact same way these drug chemists do, and then new chemicals are released into our environment that we don't have data on or testing to mitigate.

[Scarblac]

> every chemical developed by every industry in every product we're exposed to in the world

Fyi, writing it like this makes you sound like the kind of person who thinks "chemicals" are "not natural" but produced by industry and therefore dangerous and evil. Even though literally everything is made up of chemicals.

[TheSpiceIsLife]

Do you think it's safe to assume most Parkinson's suffers didn't abuse cocaine, or probably use it much if at all?

Do you think it's possible that long term moderate to heavy caffeine use could contribute to Parkinson's by the same method of action you have described?

[parkovski]

I'm not an expert on any of this, medicine is just a hobby of mine. I don't think actual Parkinson's is caused by drug abuse though, I think it's a separate disease (or maybe more than one) that ends up doing the same type of damage to the brain so the symptoms look similar. Wikipedia seems to agree, we're not sure how most people affected got it. That seems to be kind of a theme in medicine.

As far as caffeine goes, I don't think it affects dopamine that much, so it probably wouldn't have that effect on its own. I can't imagine long term heavy caffeine use would be good for you though, I just don't think it would be enough to do the same damage that drugs that directly release dopamine do. Or at least, it would do different kinds of damage - my guess is memory issues due to lack of quality sleep and high blood pressure.

[mrob]

Long term caffeine use seems to reduce risk of Parkinson's:

https://www.ncbi.nlm.nih.gov/pubmed/23879665