In the UK, community surveys indicate that one third of adults have tried illegal drugs in their lifetime, with 10% having used them in the previous year. The rates for those aged under 25 are higher, with 50% lifetime use and 33% in the previous year. At all ages males have higher rates of drug use than females (4:5 = 3–4:1). Cannabis is the most commonly used illegal drug, while community rates for the other drugs of abuse are low. Users show a variable pattern of consumption with episodic and situational use for drugs with low dependence potential and a tendency to continuous dependent use for more ‘addictive’ drugs. Among some users, particularly those in the dance scene, polydrug use is the norm with individuals consuming more than 10 different drugs. Use of illegal drugs is commoner in the young, in the lower socio-economic classes, and in those with psychiatric illness. At any one time <33% of dependent users will be in contact with treatment services; mean length of dependent use before seeking help is 9yrs.

There are as many patterns of drug use as drug user, and individual patient assessment is mandatory; nonetheless a number of patterns of use of illegal drugs can be recognized:

• Experimental use Use of drug in order to explore effects. Common among young and heavily driven by drug availability and drug use among peers. Very common for ‘softer’ drugs (e.g. cannabis, volatile chemicals), rarer for more ‘hard’ drugs (e.g. heroin).
• Situational use Drug use limited to certain situations (e.g. parties, raves). Mainly drugs with stimulant/hallucinogenic properties.
• Recreational use Regular, but non-dependent use. May be limited in time by period of life (e.g. ending at the end of university life) or may progress to dependent use.
• Polydrug use Non-dependent use of variety of drugs. One drug may be taken to potentiate the effects of another or to manage unpleasant after-effects of drug use. Risks can be additive or multiplicative.
• Dependent use Use of a drug for which a dependence syndrome (b p. 542) has developed. Continued use may be motivated more by the desire to avoid withdrawals than by positive drug effects which may have diminished due to the development of tolerance. Tendency is for the use of the dependent drug to predominate, with other drugs being taken only if the primary drug is unavailable.
• Dual diagnosis Drug users who also suffer from a major mental illness. An important group for therapeutic intervention.

Categories of drugs of abuse

• Opiates: e.g. heroin, dihydrocodeine, methadone, codeine, buprenorphine, pethidine.
• Depressants: e.g. BDZs, barbiturates, alcohol, GHB.
• Stimulants: e.g. amfetamines, cocaine, MDMA.
• Hallucinogens: e.g. LSD, PCP, mushrooms, ketamine.
• Others: e.g. cannabis, volatile substances, anabolic steroids.

Street slang associated with drug misuse

Street drug name

• Acid
• LSD
• Adam
• MDMA
• Angel dust
• PCP
• Billy
• Amfetamine
• Blow
• Cannabis
• Brown
• Heroin
• C, Charlie, Coke
• Cocaine
• Crack
• Freebase cocaine
• Dope
• Cannabis
• Downers
• Depressant drugs
• E, Ecstasy, Eccies
• MDMA
• GBH, grievous bodily harm
• GHB (gammahydroxybutyrate)
• Gear
• Heroin
• Grass, hash
• Cannabis
• Jellies
• Temazepam
• Marijuana
• Cannabis
• Mushies
• Psilocybin mushrooms
• Poppers
• Volatile nitrates
• Roids
• Anabolic steroids
• Roofies
• Rohypnol®
• Skag
• Heroin
• Skunk
• Potent form of cannabis
• Smack
• Heroin
• Snow
• Cocaine
• Special K
• Ketamine
• Speed
• Amfetamine
• Sulph
• Amfetamine
• Uppers
• Stimulant drugs
• Vallies
• Diazepam
• Vitamin K
• Ketamine
• Whizz
• Amfetamine