Antidepressants: who needs them?

3. MAOIs (Monoamine oxidase inhibitors)
Group includes: Phenelzine and tranylcypromine.
Used to treat: These are used less commonly nowadays and generally when other drugs have failed. They are being superceded by more modern antidepressants.
How they work: They work by blocking the breakdown of serotonin and noradrenaline in brain cells.
Side effects: These include light-headedness, drowsiness or insomnia, headache, dry mouth and digestive problems. They interact with some foods and other drugs which can lead to dangerous changes in blood pressure.

Other options

• Other newer drugs are available that work on both neurotransmitters, such as venlafaxine, maprotiline and trazodone.
• Some people with recurring episodes of depression are treated with mood-stabilising drugs such as lithium, carbamazepine as well as an antidepressant.
• Many people are keen to try herbal remedies and St John's Wort has been marketed as an antidepressant for use in mild depression. You should be aware that there is no standardised concentration of the active ingredient in the various preparations, so you can get different doses if you switch brands. You should always tell your doctor if you plan to take St John's Wort because it can interfere with the breakdown of other drugs such as drugs for epilepsy, the contraceptive pill and some heart medication.