Updated with added text and information in 2011, from a BP article in ISSUE 2
As you may know from our first issue, our Science on Substances feature is going to try to keep you informed about the variety of drugs that are currently involved in research trials around the world. Drugs used for detox, maintenance and abstinence, drugs that get you stoned and drugs used for your health and wellbeing, we’ll try and explain them all. This issue we introduce naltrexone…
There has been quite a lot of interest in naltrexone, not just in the UK but around the world. However, it is not just a single treatment option. There are various ways of using naltrexone – as part of a ‘rapid’ detox and as a daily dose to maintain abstinence. So, this issue we thought we should introduce naltrexone – its origins, its uses and its future.
What is Naltrexone and How Does it Work?
For heroin, (and other opiates such as methadone, morphine, palfium, codeine etc), to produce their effects – and get you stoned – they need to be able to attach themselves to small areas in the brain and nervous system called receptor sites. Naltrexone not only blocks these receptor sites, which prevents any opiates from working, but also displaces or removes any existing opiates that currently occupy those sites. Such drugs are called ‘opiate antagonists’ – they antagonise (to put it mildly!) any opiate. This means that if you take naltrexone when you have an opiate ‘habit’, you will find yourself withdrawing quickly and intensely as the opiates are rapidly (rather than slowly) removed from your receptor sites, and your body reacts to their absence. However, if you’ve already detoxed, taking naltrexone may help keep you abstinent as using heroin simply will not work. Naltrexone is sometimes referred to as a ‘non-drug’ because it doesn’t really have any effect other than blocking the effects of opiates. Naltrexone is long lasting – from 24 to 72 hours depending on the dose, and it comes as a tablet, or as an implant. It is closely related to Naloxone (or Narcan), the ‘pure’ opiate antagonist which doctors use for opiate overdoses; but naloxone only works when injected and lasts for only a short time – less than an hour.
The Origins of Naltrexone
Naltrexone is a relatively new drug in the UK, becoming available in 1985 and receiving its product license in 1988. However, it has been used in the US since the early 70’s when Nassau County Jail (Long Island) initiated the Narcotic Antagonist Jail Work Release Program. Non-violent prisoners with a history of opiate misuse were allowed out during the day to attend work/training courses as long as they were administered naltrexone regularly (in tablet form). Unfortunately, as addicts were relegated to the bottom of the jails ‘trust ladder’ this was the only way these prisoners (the majority in Nassau County Jail) would ever have been admitted to this type of programme. The use of Naltrexone was pioneered in this country by Dr. Colin Brewer at the Stapleford Centre. Drawing on American experiences, he used it along with ‘strong sedation’ to provide users with greatly accelerated detoxes that were over in 48 – 72 hours and felt less unpleasant than traditional 14 – 21 days reducing methadone regimes. Doctors at the University of Vienna in Austria then developed the Ultra Rapid Detox technique using naltrexone with a short general anesthesia so that patients were unconscious for most of the detox. Details of this technique were first published in 1988. Dr Brewer further developed the technique resulting in a compromise between the Ultra Rapid and Rapid detox by using naltrexone and ‘strong sedation’ to provide users with greatly accelerated withdrawals without the added expense and intensive nursing that was required using anesthesia. The idea behind naltrexone is that if an opiate user can stay ‘clean’ for some time, then it is easier for people to learn to change their drug-using behaviour patterns. If heroin no longer ‘works’ then the user will stop scoring and stop hanging around drug using and places friends. But naltrexone has its detractors. Freudian types and others, who believe that people use drugs because of personal and emotional problems, say that naltrexone will do nothing to confront or deal with such issues. However, it is now thought by many that the problems many drug users have are a result of their addiction and not the cause. Therefore, if a person can be kept straight for a while, many of their ‘problems’ may disappear. However, it is worth remembering that naltrexone only works for opiates and not other drugs such as amphetamines, barbiturates or cocaine.
Naltrexone and its Uses (note: prices from 2000-2001
The main use of naltrexone is for the treatment of alcohol dependence. After publication of the first two randomized, controlled trials in 1992, a number of studies have confirmed its efficacy in reducing frequency and severity of relapse to drinking.The multi-center COMBINE study had recently proven the usefulness of naltrexone in an ordinary, primary care setting, without adjunct psychotherapy.
Naltrexone and Alcohol
The main use of naltrexone was actually for the treatment of alcohol dependence. After publication of the first two randomized, controlled trials in 1992, a number of studies have confirmed its efficacy in reducing frequency and severity of relapse to drinking. The standard regimen is one 50 mg tablet per day. Initial problems of nausea usually disappear after a few days, and other side effects (e.g., heightened liver enzymes) are rare. Drug interactions are not significant,unless you are an opiate user as well of course. Naltrexone has two effects on alcohol consumption. The first is to reduce craving while naltrexone is being taken. The second, referred to as the Sinclair Method, occurs when naltrexone is taken in conjunction with normal drinking, and this reduces craving over time. The first effect persists only while the naltrexone is being taken, but the second persists as long as the alcoholic does not drink without first taking naltrexone.
Naltrexone tablets - 50 mg tablets taken daily. Of course, it only works as long as you take it – which is why clinics stress the importance of having someone to supervise the taking of the tablets. Naltrexone tablets are available on the NHS and can be prescribed by any doctor.
Advantages – Easily available and relatively cheap.
Disadvantages - Only work if you take them.
Naltrexone Implant - inserted after any detox to maintain abstinence. A one inch incision is made under local anaesthetic in the lower abdomen or the back of upper arm. They are about 1.4cm in diameter and approx 9mm thick. Effects last from 6 – 12 weeks, and then patients need the implant renewed.
Advantages - You can’t forget to take it, which makes relapse on opiates practically impossible, (good for those who don’t have someone to support them).
Disadvantages - minor surgery and a small scar, occasional infection/inflammation at site, four times more expensive than tablets and not currently available on the NHS. Naltrexone implants have not been produced by a major drug company and should still be regarded as experimental. COST only available privately – approx £ 370 for outpatient insertion).
Rapid Opiate Detox Under General Anaesthesia – (NOTE: as of 2011, this has actually become a rather questionable procedure by many doctors and academics – and opiate users. If you are considering this treatment, BP would urge detailed research into the subject and to seek advice from others in drugs the field.) Premedication is prescribed 12 hours before the procedure starts. After further premedication with anti-withdrawal drugs and sedatives, naloxone is used by injection to detach the opiates from the receptors in the brain – speeding up the withdrawal process. Instead of taking 2-5 days for withdrawals to peak, the worst of the symptoms are over in a few hours. During this acute phase, patients are fully anaesthetised in an intensive care unit for 4-6 hours, then kept sleeping for up to 14 hours. Rapid detoxification under general anaesthesia involves an unconscious patient and requires intubation and external ventilation. Many patients can return home the following day (with supervision) whilst some may need a second day of nursing. Doesn’t completely eliminate withdrawals but once you are awake, you start to feel better rather than worse. Out-patient follow-up is usually included.
Advantages - Believed to be more comfortable than other methods, quickest return to work, naltrexone implants can also be inserted whilst anaesthetized.
Disadvantages - always inherent risk with general anaesthetic, some users awake still feeling sick, but these symptoms do get better. Procedure is expensive, potentially risky (has been fatal) for those people with bad health problems.
COST: £ 3700, a bit more if you are receiving the implant as well.
Rapid Opiate Detox Under Sedation (Also called 5 Day Detox) With this method you are in hospital for about 5 days. If you’re on methadone, you may be required to transfer to morphine or other opiates a week beforehand. After admission you are given generous amounts (depends on your interpretation of generous!) of sedatives and anti withdrawal drugs. After 3-4 days naltrexone is started and rapid withdrawals commence. Aftercare included.
Advantages – no anaesthetic only sedation so lower risk to patient, most people have little recall of event, it’s a lot cheaper than general anaesthetic.
Disadvantages -over sedation is avoided so it may not always control withdrawals – this causes some patients to leave without completion. At least a week is needed off work and there is some discomfort. Mixed reviews by users.
COST: about £2250
A version of this technique can also be done at home, with clinics providing a nurse, or (cheapest of all) a friend to act as carer and supervise the person whilst they are sedated. This way it is much less expensive. COST £ 150 – £ 1250 depending on the facilities used. (NOTE: By 2011, BP was not able to verify whether at home procedures still took place. Check The Stapleford Centre, London for more info.)
Some medical insurance companies may cover the cost of inpatient treatments and implants and local NHS health authorities are sometimes willing to pay for them.
Subutex and Suboxone
Many NHS GP’s also prescribe naltrexone tablets to aid abstinence (check out subutex – a partial agonist containing the drug buprenorphine, which could be called a half way version – see Subutex on our Substances webpage. Also, there is Suboxone – just like Subutex but with a tiny amount of Naloxone in the pill, which works only if injected; in other words, its aim is to discourage people from injecting their buprenorphine pills.) See our Substances page for BP’s take on Suboxone.
Naltrexone and it’s future
Naltrexone is used in many countries such as Britain, Australia, America and Israel and is currently to be seen making its way into other drugs – or rather, its close cousin Naloxone – which is now mixed with the drug buprenorphine – to become Suboxone. And Naloxone is also undergoing trials coupled with methadone, again, to deter people from injecting their methadone.In some countries such as the United States, an extended-release formulation is marketed under the trade name Vivitrol, which has been discussed more recently (2011). Also in the US, Methylnaltrexone Bromide, a closely related drug, is marketed as Relistor (US) for the treatment of opioid induced constipation (interesting use for Naltrexone but it makes sense as it excels in expelling opiates from the brain, and certainly does bring on the urge to go to the toilet!).
Depot injectable naltrexone (Vivitrol, formerly Vivitrex, but changed after a request by the FDA) was approved by the FDA on April 13, 2006 for the treatment of alcoholism. The medication is administered by intra-muscular injection and lasts for up to 30 days. Clinical trials for this medication were done with a focus on alcohol, presumably due to the larger number of alcoholics that it could be used to treat; however, however, a safety study for the off-label use of the injection for opiate addicts was also run. This was found to be a successful use of the medication in patients who were single drug users, as it seemed that multi-drug users would generally decrease their opiate use but increase their use of other drugs (i.e. cocaine) while on the injection (we know that story…). Other studies, however, provide preliminary evidence that naltrexone with the right protocol can be effective in treating cocaine addiction.(BP will look into this further).
While it may help those who are really determined to stop using, it is always important to realise that the battle is only half fought by naltrexone. It stops the effect of the opiate drugs which can of course be a huge help, however it does not stop the urges for them. And sometimes, those urges can be overwhelming and have lead to people taking out their implants themselves, taking extremely high doses of opiates in order to ‘ get over’ the naltrexone, or end up with habits on other drugs such as sleeping pills etc.
People have also talked about their experiences of depression when taking Naltrexone, and while we aren’t sure just what happens in terms of our delicate brain chemistry when taking this drug, it does perhaps make sense that this could be an issue however, it is often the issue when people stop using opiates and have to tackle living their lives without them.
As previously stated, if you’re on methadone it is better to transfer to another opiate before detoxing because methadone can make withdrawals more difficult, certainly they will take longer. Fears have also been raised about pain relief options while on naltrexone treatment. The bottom line is, that if you are in a serious car accident etc and need some immediate pain relief, you will have to wait approx 3 days to a week before you could feel any opiate based pain killer such as morphine. In the meantime you would have to make do with non opioid analgesics (ketamine, nitrous oxide etc) which are known to be weaker than opiate based drugs in terms of pain relieving capabilities. This can and has endangered lives.
Naltrexone’s side effects are said to be very mild. You don’t experience any withdrawal symptoms when you stop taking it. Adverse reactions such as; difficulty sleeping, anxiety, abdominal pain, nausea and headaches and some reports of severe depression – have been reported but might not necessarily be caused by the medication, they could be related to post detox blues…But depression has been cited a lot by our peers certainly – and from a medical point of view its quite likely that because of the way it affect endorphins, depression is very likely. Make sure you have loved ones around whenever possible.
More information available from Dr C Brewer of the Stapleford Centre
0171 823 6840. References ; NUAA NEWS Vol 25,27 (1998), Stapleford Centre, Brewer, C. (ed) (1993) ‘Treatment Options In Addiction; Medical Management of Alcohol and Opiate Abuse’ The Royal College of Psychiatrists, Gaskell, London SW1
- No Gender Difference In Response To Naltrexone As Treatment For Alcohol Dependence (medicalnewstoday.com)
- Men and women respond equally to naltrexone as treatment for alcohol dependence (physorg.com)
- What About Low-Dose Naltrexone for Rheumatoid Arthritis? (everydayhealth.com)