Antidepressants

Antidepressants are thought to work by increasing chemicals in the brain linked to your mood. They usually take a few weeks to have an effect.

Antidepressants can cause side effects, although not everyone gets them. Most should improve after a few weeks, but sometimes they carry on.

There are different types of antidepressant. You may find some work better for you or cause fewer side effects.

Most adults can take antidepressants, and some can be taken if you're pregnant or breastfeeding. Your doctor will explain the benefits and any risks.

Antidepressants may be affected by alcohol, other medicines, St John's Wort, and some types of food or drink. Check the medicine's leaflet.

Antidepressants are a type of medicine mainly used to treat the symptoms of depression, as well as other conditions.

Antidepressants can be used to treat conditions including:

• obsessive compulsive disorder (OCD)
• post-traumatic stress disorder (PTSD)
• generalised anxiety disorder (GAD)
• panic disorder
• social anxiety (social phobia)
• bulimia
• phobias
• dementia
• fibromyalgia or nerve pain
• migraine
• bedwetting in children

Antidepressants usually take 1 to 2 weeks to start having an effect and can take up to 8 weeks to work fully.

If you're prescribed antidepressants, you'll usually take them for at least 6 months after you feel better.

How antidepressants work

It's thought antidepressants work by increasing levels of chemicals in the brain called neurotransmitters.

Some neurotransmitters, like serotonin and noradrenaline, are linked to mood and emotion.

The main types of antidepressant are:

• selective serotonin reuptake inhibitors (SSRIs) – these are the most widely used type of antidepressants
• selective noradrenaline reuptake inhibitors (SNRIs)
• tricyclic antidepressants (TCAs)
• monoamine-oxidase inhibitors (MAOIs) – these are now rarely used to treat depression

There are also several other types.

All types of antidepressant generally work as well as each other to treat symptoms of depression. But there are differences in who can take them and the side effects.

Some people find certain types work better for them, cause fewer side effects or cause side effects that are easier to deal with.

SSRIs will usually be the first type prescribed because the side effects are generally easier to manage, and they are less likely to cause serious problems if you take too much of the medicine.

If you're finding side effects hard to manage or do not feel your medicine is helping you, talk to your doctor.

Not all antidepressant medicines are listed here. If you cannot find your medicine, check the leaflet that comes with your antidepressant or ask your doctor or pharmacist.

Like all medicines, antidepressants can cause side effects.

Most side effects should ease after a couple of weeks as your body begins to get used to the antidepressant, but some may carry on.

The possible side effects depend on the type of antidepressant you're taking.

When you first start taking antidepressants, you will be seen by a doctor every 1 to 2 weeks. They will check with you to see how the medicine is working and how you're finding any side effects.

It's important to continue treatment as it can take several weeks until your symptoms start to improve. Talk to your doctor if you're finding side effects hard to manage.

Some common side effects of antidepressants include:

• mood changes – like feeling more angry or emotionally numb
• feeling agitated, confused, shaky or anxious
• difficulty sleeping
• weight gain
• headaches
• dry mouth
• blurred vision
• feeling or being sick
• feeling dizzy, drowsy or very sleepy
• loss of appetite
• indigestion and stomach aches
• diarrhoea, constipation or problems peeing
• sweating more than normal
• heart rhythm problems – like palpitations or a fast heartbeat
• problems with sex – such as low sex drive, finding it difficult to orgasm, or finding it difficult to get or keep an erection

It's not common, but some people may have suicidal thoughts or an urge to self-harm when they start taking an antidepressant medicine.

People aged 24 or under, or who have had these thoughts before, may be most at risk.

Call 999 or go to A&E immediately if you feel like you want to end your life or harm yourself at any time.

These are not all the possible side effects of antidepressants. Some side effects are rare but serious and you may need urgent medical help.

Always check the information leaflet that comes with your medicine.

Most adults can take antidepressants.

They're usually not recommended to treat depression in children and young people under the age of 18, although sometimes they may be used along with another type of treatment.

Some antidepressants can be taken if you're pregnant. Your doctor will help you understand the benefits and risks of taking antidepressants if you're pregnant so you can decide on the best treatment for you and your baby.

Some antidepressants can be taken while breastfeeding if your doctor or health visitor says your baby is healthy.

Taking some antidepressants with alcohol, some foods or some other medicines can cause side effects and is not recommended.

It can cause problems if you take antidepressants with things such as:

• alcohol – this can make your symptoms worse, or make you feel sleepy or dizzy
• some other medicines – including non-steroidal anti-inflammatory drugs (NSAIDs), and other antidepressants
• some types of food or drink
• drugs like cannabis or ketamine
• St John's wort – a herbal remedy sometimes taken for mild depression

Check the leaflet that comes with your medicine to see if there is anything you should avoid while taking it. Always ask a pharmacist or your doctor if you're unsure.