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    What are antidepressants?

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      Bottle of antidepressant pills

      If you’ve been feeling depressed, and you think you need help, it’s a really good idea to book an appointment with your GP.

      Though we tend to think of our GPs as the people we go to for chest infections and tummy bugs, they’re also trained to offer advice and treatment for mental health issues. Your GP can refer you for therapy or counselling. They might also offer to prescribe antidepressants.

      For people with severe depression, antidepressants can be really effective. However, because this medication isn’t suitable for everyone, it’s important to get a prescription from your doctor or specialist. Read on to learn more.

      How do antidepressants work?

      Antidepressants work by affecting the neurotransmitters dopamine, noradrenaline or serotonin. Neurotransmitters are the body's chemical messengers: they are helping to transmit messages between (brain) cells.

      You may find that taking antidepressants helps you feel happier and less worried, and that you can get back to your daily routine, enjoying work, hobbies, and socialising. Antidepressants can also help ease suicidal thoughts, and the impulse to self-harm.

      However, brain chemistry is complex, and everybody is different. This is why antidepressants don’t work for everybody.

      Another thing to bear in mind is that antidepressants won’t treat the root causes of depression. This is why they’re normally given as part of a combination treatment that incorporates some kind of talking therapy.

      What are antidepressants prescribed for?

      In addition to treating depression, some antidepressants can be prescribed for anxiety, post-traumatic stress disorder (PTSD), obsessive compulsive disorder (OCD), phobias, eating disorders, and chronic pain.

      Antidepressants are usually prescribed for moderate to severe depression that's having a major impact on your day-to-day life. For mild depression talking therapy is usually offered to start with.

      How long does it take antidepressants to work?

      Antidepressants normally have to be taken for one or two weeks before you start to notice a difference. It may take one or two weeks to get used to the tablets, and you may experience side-effects , but this should all pass after 2 weeks.

      It’s important to stick it out in the first two weeks of taking a new antidepressant, and not assume that the treatment doesn’t work because you don’t feel different straight away.

      However, it’s also important to speak to your doctor if you don’t feel a change in your mood after two to four weeks. They may need to increase the dose, or change your tablets.

      If the first antidepressant you try doesn’t work for you, don’t be disheartened. Sometimes it takes a little while to find the antidepressants that suits you best.

      How long do I have to take antidepressants?

      It depends on your situation. Usually your doctor will prescribe antidepressants for at least six months, but some people might need to take them for much longer.

      What types of antidepressant are there?

      There are quite a few different types of antidepressants:

      • Selective serotonin reuptake inhibitors (SSRIs) 
      • Serotonin and noradrenaline reuptake inhibitors (SNRIs) 
      • Tricyclics 
      • Monoamine oxidase inhibitors (MAOIs) - these are very rarely used nowadays and will only be prescribed by a psychiatrist 
      • So called ‘atypical’ or ‘other’ antidepressants

      The antidepressants prescribed most commonly in the UK are SSRIs such as  

      fluoxetine (Prozac), citalopram (Cipramil), and sertraline (Lustral). SSRIs are favourable because they cause fewer side effects than other types, and there’s less risk associated with overdosing. SNRIs such as duloxetine (Cymbalta) are also commonly prescribed.

      If you don’t respond to these “standard” antidepressants, your doctor may offer you another, less commonly prescribed, type.

      What are the side effects of antidepressants?

      Different antidepressants can cause different side effects.

      In many cases, side effects will occur soon after you start treatment, but will wear off as your body gets used to the medication. For some people, however, side effects may persist.

      If you’re taking SSRIs or SNRIs, you might experience some of the following in the first few weeks:

      • Headaches  
      • Drowsiness 
      • Nausea and vomiting 
      • Problems sleeping 
      • Feeling anxious or agitation 
      • Indigestion 
      • Stomach aches 
      • Diarrhoea or constipation 
      • Loss of appetite 
      • Dizziness 
      • Loss of sex drive 
      • Sexual dysfunction (e.g. difficulty having an orgasm or getting an erection)

      Other types of antidepressant may cause slightly different side effects. Tricyclics, for instance, can cause a dry mouth, blurred vision, and night sweats.

      In rare cases, antidepressants can cause an increase in suicidal thoughts and the impulse to self-harm. If you ever find yourself thinking of self-harming or having suicidal thoughts, contact your doctor or go to the hospital immediately.

      You can learn more about the side effects associated with antidepressants in this guide by the NHS.

      How to get antidepressants

      Because antidepressants aren’t suitable for everyone, it’s important to get them on prescription from a UK healthcare professional. Trying to obtain them illegally from an unregulated source could be really dangerous.

      Your GP will probably prescribe a standard antidepressant like an SSRI, but if standard antidepressants don't work for you, or things are getting worse your GP might refer you on to a psychiatrist.

      How to take antidepressants safely

      You should only ever take your antidepressants as directed by the GP or specialist who prescribed them. If you don’t think an antidepressant is working, or if you’re getting troublesome side-effects, speak to your prescribing doctor for advice. Don't stop your antidepressants without speaking to your doctor first- antidepressants need to be reduced gradually over a few days; stopping them "cold" might make you feel even worse.

      While taking antidepressants, you’ll also need to make sure that you avoid certain types of medication or herbal remedy. Please tell your doctor about any supplements you take and also make sure you read the patient leaflet that comes with your tablets.

      If you’re taking SSRIs or SNRIs, you shouldn’t take any other medication that increases levels of serotonin in the brain, such as St John’s Wort or 5-HTP. If you do, you could “overdose” on serotonin and develop a dangerous condition called serotonin syndrome.

      For more information about medications and other substances to avoid, consult this guide from the NHS.

      Other treatments for depression

      If your doctor doesn't feel antidepressants are the best way forward at this moment in time, or if you don’t want to take medication, there are some good alternatives, including:

      In England, you can refer yourself directly for talking therapy through the NHS. Visit this page to find a service near you.

      While it’s not always easy to get yourself out of depression without help from a professional, making changes to your lifestyle can help. Changes that can boost your mood include eating a healthy and balanced diet, exercising regularly, cutting back on alcohol, and getting more sleep.

      For more help and guidance, check out the free resources available at Mind and the NHS. If you’re struggling and you need help right away, this page contains information about mental health services and helplines.

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