SSRIs (specific serotonin reuptake inhibitors) are medicines that boost serotonin levels. They are most often used to help treat some of the symptoms of depression and of anxiety. SSRIs can also help CBT (cognitive behavioural therapy) work better.
It can take up to 4-6 weeks to get the full effect of a regular dose of this type of medication.
A course of antidepressants lasts a minimum of 6 months. Though often people take them for longer, particularly if they have had recurrent problems.
SSRIs are not felt to be addictive, but if you have taken them for eight weeks or more, you may experience some (usually mild) “discontinuation” effects if you stop them suddenly. It is usual to reduce the dose gradually, over some weeks, to reduce this problem.
It is also best not to stop them 2 weeks or so before an important event – such as exams – in case your symptoms recur.
Side Effects
If they are going to occur, usually happen within the first 2 weeks of starting. They are usually mild and wear off after 2 weeks. The most common side effects(more than 1 in 10 people might get these)
| Symptom | Description | What might help |
| Nausea (and vomiting) | Feeling sick (and perhaps being sick, though this is much less common) | Take your SSRI with or after food. If you are sick for more than a day, contact your doctor. This usually improves with time – over a few days or a week or so. |
| Insomnia | Not being able to get to sleep at night. | Take your dose in the morning. It may be possible to change the time of your dose if this is still a problem, or reduce the dose a little to start with. However, if it makes you drowsy (perhaps 1 in 20 people), it can be better to take it in the evening. |
| Sexual dysfunction | Finding it hard to have an orgasm. No desire for sex. | This can also be a symptom of depression. If caused by medication it is often dose related. Discuss with your doctor. |
SSRIs may cause you to lose weight when you first start.
Another less common but potentially serious side effect of starting SSRIs are that they can make some people feel more impulsive or suicidal. If this should happen to you, you should stop taking the medication and see the doctor urgently if you feel you can’t keep yourself safe.
A modest amount of alcohol (1-2 units) can be OK while taking an SSRI, although it might make you feel more sleepy. If this happens you should not operate machinery or drive a car, if you feel your concentration/decision making ability is reduced (whether or not you have been drinking). Alcohol tends to make depression and anxiety worse, and in general should be minimised.
Your doctor will want to see you about 2 weeks after giving you a prescription for SSRI medication – even if you have made the decision not to take/continue it.