Starting an antidepressant can feel like a big step, and the first few weeks are often the hardest. Knowing what to expect, and what is normal, makes it far more likely the medicine will help.
Imagine finally asking for help with months of low mood and anxiety. You are prescribed sertraline. For the first week you feel jittery and slightly sick, and you wonder whether to stop. Three weeks later, you realise you have started enjoying things again.
What SSRIs are
Selective serotonin reuptake inhibitors (SSRIs) are the most commonly prescribed antidepressants worldwide. They include sertraline, citalopram, escitalopram, fluoxetine and paroxetine. They increase the availability of serotonin, a chemical messenger in the brain involved in mood, anxiety, sleep and appetite.,SSRIs are used for depression, generalised anxiety disorder, panic disorder, obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD), some eating disorders and premenstrual dysphoric disorder.
How long they take to work
SSRIs do not work immediately. Some people notice small improvements in sleep or energy within one to two weeks, but it usually takes four to six weeks to feel the full effect, and sometimes longer.,This delay can be frustrating, especially if side effects appear first. Your healthcare provider will usually review you within a few weeks of starting, to check how you are doing and whether the dose needs adjusting.
Common side effects
- Nausea, upset stomach or diarrhoea
- Headache
- Feeling restless, jittery or more anxious at first
- Sleep changes: insomnia or drowsiness
- Sweating
- Reduced sex drive, difficulty with arousal or orgasm
- Many early side effects settle within two weeks
Serious side effects to know about
A small number of people, particularly those under 25, have an increase in suicidal thoughts when they first start an antidepressant or change the dose. If you notice thoughts of harming yourself, or feel much worse, contact your healthcare provider straight away or seek urgent help.,Other rare but important side effects include low sodium levels (especially in older adults), increased bleeding risk when taken with anti-inflammatory painkillers or blood thinners, and serotonin syndrome when combined with certain other medicines. Signs of serotonin syndrome include agitation, high temperature, sweating, shivering, fast heartbeat and muscle twitching, and it needs urgent medical attention.
Medicines and substances to be careful with
- Other antidepressants, tramadol, triptans for migraine and St John’s wort, which can increase serotonin
- Anti-inflammatory painkillers such as ibuprofen, and blood thinners, which increase bleeding risk
- Alcohol, which can worsen depression and drowsiness
- Always tell your pharmacist you take an SSRI before buying medicines
How long to take them
For a first episode of depression, guidelines commonly recommend continuing an antidepressant for at least six months after you feel better, to reduce the risk of relapse. People who have had several episodes may be advised to continue for longer. Your healthcare provider will help you decide when it is a good time to stop.
Stopping safely
Do not stop an SSRI suddenly. Stopping abruptly, or reducing too quickly, can cause withdrawal symptoms such as dizziness, “electric shock” sensations, flu-like symptoms, irritability, anxiety, vivid dreams and low mood.,The dose is usually reduced gradually over weeks or months, depending on the medicine, how long you have taken it and how you feel. Some people need a very slow taper. Withdrawal symptoms can sometimes be mistaken for depression returning, so talk to your healthcare provider about what you notice.
Common myths
- “Antidepressants change your personality.” They aim to help you feel more like yourself, not different
- “They are addictive.” They do not cause cravings like addictive drugs, but stopping suddenly can cause withdrawal symptoms
- “They are a sign of weakness.” Depression is a health condition; treatment is not weakness
- “Medicine alone is enough.” For many people, talking therapy, exercise and support work best alongside medicine
SSRIs in pregnancy and breastfeeding
If you are pregnant, planning a pregnancy or breastfeeding, talk to your healthcare provider before stopping or starting an antidepressant. Untreated depression also carries risks, and some SSRIs are commonly used in pregnancy and breastfeeding. The decision should be made together, weighing the benefits and risks for you and your baby.
Getting the most from treatment
- Take your medicine at the same time each day
- Keep your follow-up appointments
- Combine medicine with talking therapy if available
- Stay as active as you can and keep a regular sleep pattern
- Tell someone you trust how you are feeling
- Keep a note of side effects to discuss
Frequently asked questions
Can I drink alcohol on an SSRI?
It is best to avoid or limit alcohol, as it can worsen low mood and increase drowsiness.
Will I gain weight?
Some people gain weight over time, but many do not. Talk to your healthcare provider if this worries you.
What if the first SSRI does not work?
A different dose or another medicine may suit you better. It is common to need a change.
Can I take SSRIs with the contraceptive pill?
Yes, SSRIs do not usually affect hormonal contraception.
But what if I feel worse in the first few weeks?
Some people feel more anxious or unsettled at first. This often passes, but tell your healthcare provider, and seek urgent help immediately if you have thoughts of harming yourself.
Your next step: If you have just started an SSRI, put a reminder in your diary to review how you feel with your healthcare provider in two to four weeks.
Related: Signs of depression · How to find a counsellor
Sources: National Institute for Health and Care Excellence (NG222), Royal College of Psychiatrists, World Health Organization, US Food and Drug Administration, Mind (UK).
Leave a Reply