Antidepressants are used to treat clinical depression or prevent it recurring.They can also be used to treat a number of other conditions, including obsessive compulsive disorder (OCD), generalised anxiety disorder and post-traumatic stress disorder (PTSD). Antidepressants are also sometimes used to treat people with long-term (chronic) pain.
Different types of antidepressants
Selective serotonin reuptake inhibitors (SSRIs)
SSRIs are the most widely prescribed type of antidepressants for they cause fewer side effects. An overdose is also less likely to be serious. Fluoxetine is probably the best known SSRI (sold under the brand name Prozac). Other SSRIs include citalopram (Cipramil), paroxetine (Seroxat) and sertraline (Lustral)
Serotonin-noradrenaline reuptake inhibitors (SNRIs)
Were designed to be a more effective antidepressant than SSRIs. However, the evidence that SNRIs are more effective in treating depression is uncertain. Most of the people respond better to SSRIs, while others respond better to SNRIs. Examples of SNRIs include duloxetine (Cymbalta and Yentreve) and venlafaxine (Efexor).
Noradrenaline and specific serotonergic antidepressants (NASSAs)
NASSAs may be effective for some people who are unable to take SSRIs. The side effects of NASSAs are similar to those of SSRIs, but they’re thought to cause fewer sexual problems. However, they may also cause more drowsiness at first.
The main NASSA prescribed in the UK is mirtazapine (Zispin).
Tricyclic antidepressants (TCAs)
TCAs are an older type of antidepressant are no longer usually recommended as a first-line treatment for depression. overdosage of this drug may be dangerous. They also cause more unpleasant side effects than SSRIs and SNRIs.
TCAs are sometimes taken by people with severe depression that fail to respond to other treatments. It may also be recommended for other mental health conditions, such as OCD and bipolar disorder.
Examples of TCAs include amitriptyline (Tryptizol), clomipramine (Anafranil), imipramine (Tofranil), lofepramine (Gamanil) and nortriptyline (Allegron).
Some types of TCAs, such as amitriptyline, can also be used to treat chronic nerve pain.
Alternatives to antidepressants
Alternative treatments for depression include talking therapies such as cognitive behavioural therapy (CBT).
People with moderate to severe depression are treated using a combination of antidepressants and CBT. Antidepressants work quickly in reducing symptoms, whereas CBT takes time to deal with causes of depression and ways of overcoming it.
Regular exercise has also been shown to be useful for those with mild depression.
How antidepressants work
Antidepressants work by increasing levels of a group of chemicals in the brain called neurotransmitters. Certain neurotransmitters, such as serotonin and noradrenaline, can improve mood and emotion. Increasing the levels of neurotransmitters can disrupt pain signals sent by nerves, which may explain why some antidepressants can help relieve long-term pain.
Antidepressants don’t address the cause of depression, it only lessen symptoms brought by it. In that case, antidepressants often combined with therapy to treat more severe depression or other mental health conditions caused by emotional distress.
How effective are antidepressants?
Research suggests that antidepressants may not be as effective as previously thought in cases of mild depression. However, they’re the most effective treatment in relieving symptoms quickly, particularly in cases of severe depression.
The Royal College of Psychiatrists estimates that 50-65% of people treated with an antidepressant for depression will see an improvement, compared to 25-30% of those taking inactive “dummy” pills (placebo). This means that most people do benefit from antidepressants, even if it’s sometimes a result of the placebo effect.
Doses and duration of treatment
Antidepressants are usually in a tablet form. You’ll start on the lowest possible dose thought necessary to improve your symptoms.
Antidepressants usually need to be taken for around seven days (without missing a dose) before you realize its effect. Do not stop taking it if you get some mild side effects early on. These effects usually wear off quickly.
If you don’t feel any better, four weeks after taking the medication, speak to your GP or mental health specialist. They may recommend you to take a higher or try an alternative medication.
A course of treatment usually lasts for six months, although a two-year course may be recommended for people with a previous history of depression. Some people with recurrent depression may be advised to take them indefinitely.
Side effects varies with the type of anti depressant that is being taken.
In general, the most common side effects of antidepressants are usually mild. Side effects should improve within a few days or weeks of treatment, as the body gets used to the medication.