Most adults, and a large proportion of young people in the UK, drink alcohol. Many people drink daily at levels that are likely to eventually damage their health, and/or drink such large amounts on occasion that they are in danger through physical deterioration, accidents or involvement in violence. A small percentage (but still a substantial number) become dependent on alcohol. A small, but increasing, number drink so much at one time that they poison themselves and die of an overdose.

Alcohol consumption among clients of drug services is well above the national average, and alcohol is a major contributor to illness and death for clients of drug services. Opiate users, particularly those who inject, are at much higher risk of overdose involving alcohol than the general population. Alcohol is a depressant drug that interacts with other psychoactive substances; in particular it increases the sedative effects of particular drugs, including heroin, methadone and benzodiazepines. It can also reduce the effectiveness of many medicines.

The National Treatment Outcome Research Study (NTORS) found that 33% of those entering residential treatment or community methadone programmes were drinking at levels above those recommended as safe, and at follow-up a year later a substantial proportion were still doing so. The proportion of drug users treated in the community drinking above safe limits (23%) did not alter over the year, nor did the proportion drinking daily (11%) (Gossop et al. 2000).

Drug users are at increased risk of developing a variety of problems related to their alcohol use. These include the facts that:
• those in treatment may be on prescription drugs (including methadone) which interact with alcohol in an unhelpful or dangerous way
• alcohol is metabolised by the liver – drug users whose livers are impaired through hepatitis C
(as are 30% outside London) may need to greatly reduce, or abstain from, drinking to avoid accelerating liver damage
• using alcohol and cocaine together results in the formation of coca-ethylene in the body. This has similar effects to cocaine, but lasts longer in the bloodstream and has significantly greater toxic effects on the cardiovascular system and the liver
• some people use opiates to cope with other distress in their lives – if they reduce their drug intake or go on to methadone, they may switch to heavy drinking instead and develop a dependence on alcohol
• mixing depressant drugs such as alcohol, heroin, tranquillisers, methadone or buprenorphine is particularly dangerous as they increase each other’s sedative effects – opiate users who are heavy drinkers are more likely to die from overdose than those who drink less
• alcohol use can be implicated in relapse to drug use through poor decision-making skills whilst intoxicated.