Its similarity to heroin makes methadone a useful substitute for recovering heroin addicts. Here's what you need to know about methadone;

Methadone is a synthetic drug with painkilling properties. The effects are similar to heroin, though less addictive. This is why methadone is often used as a substitute to help heroin users withdraw. It is available in various forms and strengths. Generally, it is offered as a green liquid preparation, but can also come in tablet, ampoules (for injection) or linctus form. The drug is available on prescription only, and is intended to be taken as part of a supervised reduction or maintenance programme.

What are the effects of methadone?

The effects are similar to those of heroin and include feelings of well-being, relief from physical pain and psychological unease. This is why methadone is primarily used to ease heroin withdrawal
Drowsiness can occur at higher doses
The effects last up to 24 hours, longer than heroin. This means heroin users attempting to withdraw do not need to take methadone as frequently
Withdrawal symptoms are slower to develop but last longer than heroin.

What are the risks of taking methadone?

Methadone is a very addictive drug. It may be effective in helping heroin users to withdraw, but methadone misuse can lead to dependency problems
Tolerance develops. This means the user increasingly needs more methadone to get the same effect
Side effects can include constipation, nausea, sweating and itchy skin
Unsupervised or sudden withdrawal can lead to a period of diarrhoea, insomnia, vomiting, hot and cold sweats, and cramps
Methadone is a powerful drug. Excessive doses can lead to overdose or coma. Misuse can also be fatal.
If injecting liquid methadone, sharing needles can pass on diseases such as HIV and hepatitis.

Methadone and the law:

Methadone is a Class A drug. Under the Misuse of Drugs Act, it is an offence to possess methadone without a prescription. Supply of the drug without a license is an offence under any circumstances.

Other names for methadone:

Juice, green, meth, Phy and dollies.

If you are planning to take methadone:

Stick closely to supervision instructions to avoid side-effects and other risks. For more details, consult your dispensing pharmacist or local prescribing service.

Prescription methadone users in possession of a UK driving license are required to disclose their use to the DVLA. A medical may be required to evaluate whether you can continue to be licensed to drive.

As a rule, never share needles. Sharing equipment just isn't worth the risk.