Examples: chlorpromazine, clozapine, thioridazine, haloperidol, sulpiride, risperidone.
Uses: schizophrenia, psychotic episodes, hallucinations, in low dose for anxiety.
Unwanted effects: sedation, dry mouth, blurred vision, constipation, sexual dysfunction, menstrual disturbances, dizziness, tremor, slowness, apathy, emotional withdrawal, agitation, restlessness, depression, palpitations, rashes.
Guidelines: Short-term use: severely disturbed patients in hospital and for severe anxiety. Long-term use: low doses for anxiety, schizophrenia and other psychoses. Should be withdrawn gradually.
Uses: manic depressive psychoses, bi-polar disorder, stabilising mood swings.
Unwanted effects: tremor, thirst, excessive urination, weight gain, nausea, diarrhoea, emotional flatness.
Guidelines: It is used long-term to prevent mood swings in manic-depressive illness. It is seldom withdrawn but when it is done, it should be reduced gradually.
Examples: (tricyclic, sedative) imipramine, amitriptyline, (SSRI, stimulant) fluoxetine, paroxetine.
Uses: depression, anxiety, phobias, obsessional disorders, insomnia associated with depression, eating disorders.
Unwanted effects: sedation, dry mouth, blurred vision, constipation, sexual dysfunction, dizziness, nausea, palpitations, sweating, tremor, loss of or increase in appetite, and weight gain, worsening depression, suicidal thoughts, rashes, confusion, dependence.
Guidelines: They are usually prescribed for three months to a year and often longer. The dose is increased gradually until the desired antidepressant effect is obtained, and to allow for tolerance to side-effects to develop. This usually takes from two to four weeks. They should be withdrawn gradually and there is a recognised withdrawal syndrome.
Examples: diazepam, lorazepam, temazepam, nitrazepam. (Similar drugs: buspirone, zopiclone.)
Uses: anxiety, insomnia, panic attacks, muscle relaxation, stress.
Unwanted effects: nausea, constipation, headache, tinnitus, dizziness, sexual dysfunction, tiredness, drowsiness, lethargy, poor concentration, impaired memory, anxiety, depression, agoraphobia, panic attacks, aggressive outbursts, dependence.
Guidelines: Anxiety: They are ‘indicated for the short-term relief (two to four weeks only) of anxiety that is severe, disabling or subjecting the individual to unacceptable distress’ (BNF section 4.1). Insomnia: They ‘should be used to treat insomnia only when it is severe, disabling or subjecting the individual to extreme distress’ (BNF section 4.1). They should be withdrawn gradually.
Methyphenidate Hydochloride (Ritalin) (stimulant).
Use: Attention-deficit hyperactivity disorder in children.