Naltrexone Drug Info

Naltrexone (Maintenance Treatment)

What is naltrexone?

Naltrexone is a drug prescribed to help people maintain abstinence after they have withdrawn (detoxified) from heroin or other opioids. It is also used in an experimental treatment to bring about rapid withdrawal from opioids. Naltrexone has also been used as a treatment to support abstinence for people who are dependent on alcohol.
This information explains the use of naltrexone to assist people in maintaining abstinence from heroin use.
What does naltrexone do?
Naltrexone is classed as an opioid antagonist. It works by blocking the opioid receptors in the brain and therefore blocking the effects of heroin and other opioids. It can assist in maintaining abstinence from heroin because the person is aware that they cannot achieve a ‘high’ from using heroin. Therefore, any money spent on heroin will be wasted. It does not directly stop a person wanting to use heroin, although it may reduce or prevent cravings in some people. You cannot become physically dependent on naltrexone and it does not produce any euphoric effects.
How effective is naltrexone?
There have been a lot of media reports on naltrexone, often describing it as a ‘miracle cure’ for heroin. There is, however, general agreement from drug professionals that the effectiveness of naltrexone treatment is very much dependent on:

  • the person’s particular situation, including their level of commitment to staying off heroin and the level of support available to them and
  • it being one part of a comprehensive treatment program, which includes regular counselling.

In fact, recent studies have suggested that many clients do not remain on naltrexone treatment and will often return to heroin use. More studies are currently being conducted that may provide a clearer picture of naltrexone’s effectiveness. It is important to recognise that naltrexone treatment may be effective for some people, but will not suit everyone.

How do you know if naltrexone maintenance treatment is right for you?

Naltrexone is one of a number of treatments for heroin dependence. Other treatments include:

  • Methadone maintenance
  • Withdrawal/detoxification (residential or home-based/medical or non-medical)
  • Counselling (outpatient or as part of residential rehabilitation).

It is strongly recommended that a person wanting to remain abstinent from heroin engages in a treatment program that addresses both the physical and psychological aspects of drug dependency. This usually includes combining various treatments, such as methadone maintenance with counselling, or progressing from withdrawal to counselling/rehabilitation.
A doctor or drug counsellor that spends time assessing the person’s situation and explaining the different treatment options will more likely recommend a program that is appropriate for that person.
If applying for the naltrexone program, see a doctor who is experienced in this treatment (your statewide drug phone service can provide an appropriate referral).
To be eligible for naltrexone treatment, the following needs to be considered:

  • The person must be free of heroin and other opioids for 7 – 10 days, or 10 days for methadone, before commencing naltrexone maintenance treatment, otherwise there is a risk that the individual may experience acute, instant withdrawal.
  • Existing liver conditions, such as acute hepatitis, may exclude a person from naltrexone treatment.
  • If a woman is pregnant or breastfeeding further advice should be sought, as it has not been established that using naltrexone during pregnancy is completely safe.
  • People who are highly motivated to be opioid free and have support from family and/or friends are more likely to benefit from the treatment.

Other considerations
Having the right support and environment is crucial in helping the person give up and, perhaps more importantly, stay off heroin.

  • Support.
    The support of family, friends, doctor and/or drug counsellor (practical and emotional support) is very important to help the person through the process of withdrawal.
  • To be away from drugs. To be out of the environment in which drugs are readily available (this may mean giving up old friends, moving to a different area)
  • To understand his or her drug use.
    To understand why the person uses a particular drug, what might trigger them to using, what other emotional and practical issues they might be facing (a drug counsellor can help the person through this).

What are the side effects?

Naltrexone is generally well tolerated, however some side effects have been reported. Most of these symptoms occur very early in treatment — the first week or so. It is important to note that some of these effects may be due to the combined experience of withdrawal from opioids and taking naltrexone.
Most commonly reported:
Difficulty in sleeping, anxiety, nervousness, abdominal pain/cramps, nausea and/or vomiting, low energy, joint and muscle pain and headache.
Less commonly reported:
Loss of appetite, diarrhoea, constipation, increased thirst, increased energy, feeling depressed, irritability, dizziness, skin rash, delayed ejaculation, decreased potency, and chills.

What does the treatment involve?

Treatment involves taking a prescribed amount of naltrexone for as long as it is perceived to be required; the length of the program depends on the individual’s situation. The tablets are taken orally, once a day, the usual dose being 50mg, or every couple of days at a higher dose (e.g. 100mg on alternate days or 150mg every three days). Daily doses are often recommended in order for the person to develop a routine, and to keep a stable level of naltrexone in the blood. Often a carer, family member, doctor or pharmacist supervises the administration of the dose.
The Naloxone (Narcan) Challenge Test (NCT)
Following abstinence from opioids for a period of 7-10 days, and after a negative urine test has been achieved for opioids, a naloxone (Narcan) challenge test is usually administered by a doctor to determine the remaining degree of physical dependence on opioids.
Naloxone is injected into the individual and they are then monitored for approximately 20 minutes to assess any signs of withdrawal. If moderate to severe withdrawal symptoms are identified, the test can be undertaken again 24 hours later. If the symptoms indicate only mild withdrawal, the first dose of naltrexone can be provided.
Agitation, parathesia (temporary numbness/pins and needles) has been infrequently reported with the use of naloxone.

The greatest risk associated with naltrexone is when heroin is used either after a naltrexone dose has been skipped or if a person stops taking naltrexone altogether. While the person is on naltrexone, tolerance to heroin decreases. Therefore, if heroin is used (and the effects of naltrexone are either diminished or worn off completely), the risk of overdosing from heroin is greatly increased. People who are planning to use heroin after being on naltrexone should consider themselves ‘new’ users. Overdose may occur if the person uses the same or even a smaller amount of heroin compared to what they did before being on naltrexone. In Australia, there have been a number of naltrexone-related deaths, due mainly to this reason.

If a naltrexone dose is skipped, it is important to remember that the blocking effect wears off gradually (for example, the usual daily dose of 50mg will wear off in 24-72 hours). Therefore, if heroin is used in the meantime, a ‘high’ may not be achieved immediately and there may be a temptation to use again and/or increase the dosage. As the naltrexone slowly wears off, the ‘full’ effects of all of the heroin can be experienced, increasing the chances of overdose.

Emergency cards
Given that naltrexone blocks the effects of opioids, if painkillers are required which are opioid based, they will not be effective. It is important that doctors/medical staff are aware if an individual is taking naltrexone so that opioid-free drugs can be administered. An Emergency Card is a useful method of alerting medical staff that an individual is taking naltrexone.

What does it cost?

Currently naltrexone treatment for heroin is relatively expensive (approximately $200 – $370 per month). The cost of treatment can run into the thousands depending on the time the person is on the treatment, any other services utilised (such as counselling), and whether the service is privately run or a public service.

How can I support someone who is on the naltrexone program?

Supporting a friend or family member on the naltrexone program requires providing both emotional and practical support. If you take on this role you need to establish a clear agreement with the person on the naltrexone program about what this will (and will not) involve. You and your family member/friend should first discuss and agree on issues, such as the your role in informing the doctor if problems arise. You also need to think carefully about your limits regarding the type of support you can give to the person on treatment. Be careful not to overstep what you feel you are willing and able to give and remember to take care of yourself, which includes arranging support for you.

Supporting your family member/friend on the naltrexone program may include:

  • Being committed to supervising the naltrexone dose for the duration of the treatment
  • Knowing what to do in the event of an overdose
    Encouraging your friend/family member to develop their friendships and support networks, to get involved in positive, healthy activities (such as taking a class, joining a support group, being active)
  • Going with your friend/family member to appointments (doctors, counsellors)
  • Attending couple or family counselling if appropriate.

How can I find out more?

Before a person goes on any drug treatment program, it is important that all the information has been explained to them (and, where appropriate, carers, such as family, friends etc) by a doctor experienced in drug treatment and/or a drug counsellor. This includes the length of the program, how much it costs, what other supports are included or recommended, all the risks and side effects, and any other health issues to consider.