What people don't understand about MMT is that methadone is not merely a substitute but a treatment to prevent relapse like antabuse. Here in Europe it's not a moral goal itself to get people off methadone because study after study for the last 30 years has shown it's the only thing that can reduce unsafe drug use, disease and crime. Short of pharmaceutical heroin of course, which will be started to be dispensed in my country very soon.

If you take an ex-addict off his methadone, he will very quickly fall back to chronic heroin use. Keep him on it and he will only do it occasionally. The people you often see come to pick up their methadone looking stoned are very rarely on too big a dose(more often the dose is too small). They are most often intoxicated by combinations of benzodiapines and cannabis. The main side-abuse problem with methadone is benzos.

The tragic fact that people often don't realise is that opiates cause irreversible downregulation of the mu-receptors. Once you have been taking an opiate for a number of years, you cannot go back to point zero. Your body has been changed and it will not return to normal by itself. Tapering methadone down makes no sense since you will be having very few opiate receptors left in your body, too few for your endogenous endorphins to bind to leaving you chronically deprived. You will have to fill in the gap with an opiate such as methadone or buprenorphine for the rest of your life. If you could see inside an addicts body you would know what damaged state he is in and why any call for abstinence is futile.

I realise that the above is more or less off topic but I've written it to let people know what they are going into when taking an opiate on a daily basis, whether it's for pain or pleasure.

I believe it's firmly established that tolerance stays to some degree. Most medical textbooks on opiate treatment recognise the difference between people that have never been treated with opiates('opioid naive') and those who have. Those who are opioid naive require significantly lower doses because of their initial sensitivity.

The mechanism is simple receptor downregulation and opiates share this problem with many other classes of drugs.

A similar problem in reverse occurs with antipsychotic drugs. Initially they suppress symptoms well by blocking dopamine receptors. But even from day one the brain will increase both dopamine receptor density and synthesis. Heavy dosing with neuroleptics can raise both with 100-200% in less than a month. This is most likely what causes TD and other disabling side effects. These upregulations are also irreversible. Note that irreversible in this context means it will not reverse by itself.

Homeostasis is the great nemesis of medicine. Homeostasis cannot be beaten but it can be manipulated.

Naltrexone/naloxone can actually reset your sensitivity to zero or even increase it further. There is nothing spectacular about it. But in practice this treatment option is limited to very few patients and has more or less been abandoned in favour of mixed agonist/antagonists such as buprenorphine. The primary reason is that people who had their opiate sensitivity restored would often end up overdosing because they took the dose they used to. Naltrexone has to be taken on a daily basis and even an implant is not foolproof since there will be fluctuations in blood levels.

The second reason is that chronic treatment with naltrexone naturally has a very bad impact on your well being. You can't just block out a major hormone and expect to be able to live normally. The side effects of chronic blockade is depression, asthenia, low motivation, hypersensitivity to pain, shivering and a whole lot of subtle symptoms. This is why buprenorphine is preferred over naltrexone, it is also an agonist so it doesn't cause these problems as much.

So you cannot keep a person on naltexone indefinetely. He has to get off after a few months, otherwise he will be a wreck prone to other types of abuse such as cocaine. Then you will have a polyabuser instead.

Naltrexone can reverse tolerance but is only suitable for users that are highly motivated to start a completely new life.

I don't know much about ibogaine but it sounds very promising. I'm convinced it can reduce both tolerance and withdrawals but the question is how much. I saw an example on TV about a guy who got off a fairly large methadone cold turkey using ibogaine. It was obvious that he did not suffer the expected symptoms. It should have made him a shivering wreck but from what I could see he suffered only fatigue and a runny nose. I would like to see it being applied on a larger scale but it's being complicated by its legal status. I don't understand why it must be illegal, it has little if any abuse potential and is pharmacologically related to reserpine.