Using alcohol or other drugs does not in itself mean that a person has a substance use disorder. However, alcohol and drugs can be addictive and there a number of signs to indicate that a person may have a problem, including:

• a tolerance for the substance – needing to drink more alcohol or use more drugs to get the same effect;
• symptoms of withdrawal – for example, when a frequent or heavy drinker suddenly stops or significantly reduces the amount of alcohol drunk they experience an increased heart rate, faster breathing, nausea and vomiting, shaking, sweating, agitation and anxiety, disturbed sleep or hallucinations;
• using larger amounts of the substance;
• problems with cutting down or controlling how much is used;
• spending a lot of time thinking about, using or recovering from use of the substance;
• giving up or reducing important social, occupational or recreational activities because of substance use;
• continued use even when it is interfering with work, family or relationships.

Some people experience problems with both their mental health and their use of alcohol and/or other drugs, and this relationship is complicated:

• a mental health problem may trigger the use of alcohol or drugs, for example someone may drink to cope with feelings of anxiety or depression and although this may bring some relief in the short term, long-term alcohol misuse or severe alcohol withdrawal may increase anxiety levels or make the depression worse;
• the use of, or withdrawal from, alcohol or drugs may trigger a mental health problem, for example regularly drinking too much can lead to depression, or using cannabis may trigger schizophrenia in a vulnerable person;
• substance use may make an existing mental health problem worse.

Alcohol

Some people drink alcohol because they believe it can alter their mood and feelings, or help them cope with situations or emotions they find difficult. However, alcohol is a depressant drug. It affects how the brain works, slowing down the central nervous system and altering mood and feelings. A person who is feeling anxious or depressed is likely to feel worse under the influence of alcohol.

There is a high incidence of mental health problems in people who have an alcohol use disorder and a high incidence of alcohol use in those with mental health disorders. Some people use alcohol to get relief from their symptoms of mental health problems. This can lead people into a destructive cycle of increasing alcohol use. Alcohol can cause the symptoms of psychosis, particularly hallucinations and paranoia. It is also linked to low moods and physical health problems during withdrawal.

Alcohol interacts badly with many medications used to treat mental health disorders. It is essential that people let their doctor know how much they drink so they can be prescribed the correct type and dosage of medication.

To find out more about how alcohol and its effects go to www.knowyourlimits.info

Drugs
Many people misuse drugs (illegal or over the counter) because they want to alter their state of mind. However, using drugs can also produce unpredictable and undesired effects such as anxiety, paranoia, psychosis, depression, memory loss, sleep problems, panic and irritability.

Generally, the symptoms will wear off once the use of the drug stops. However, this can take anything from a few hours to several days and the person can be left feeling low or anxious. Long term regular use of any drug can increase the risk of side effects and dependency.

The use of drugs can lead to problems in people’s daily lives which can worsen or complicate mental health problems. These problems may be to do with lack of money, work, housing, or contact with the police or criminal justice system.

The use of cannabis may increase the risk of developing schizophrenia in those who are vulnerable to the disorder and young people may be at particularly at risk.
People with existing mental health disorders such as depression, anxiety and schizophrenia risk complications by taking drugs which have not been prescribed. These may react with their prescribed medication and interfere with treatment or make the illness worse.

What causes substance use disorders?
There are a number of risk factors which may increase the risk or trigger the development of a substance use disorder. These include a combination of genetics, environment and behaviour, for example:

• having a biological parent with an alcohol use disorder;
• difficult life situations – homelessness, relationship breakdown, bereavement, parental conflict/separation/divorce, physical or sexual abuse, neglect;
• poor monitoring or supervision during childhood or adolescence;
• psychological distress or having a psychiatric, conduct or emotional disorder;
• living in an area where the substance is readily available and socially acceptable;
• unemployment, truancy or criminal activities.

You can read more about young people, alcohol and drugs here.

If you are concerned about alcohol or other drugs speak to your GP or other health professional.

For further information visit Royal College of Psychiatrists website.