Side effects
Some side effects that appear should get better after a few days. If they do not, you should go back to your doctor.
If you get any side effects not listed here please look at the patient leaflet in the medicine pack.
Do not stop taking the tablets until you talk to your doctor, or you may get withdrawal symptoms as well.
Very common side effects (affecting more than one in ten people) include:
- nausea (feeling sick), which is why you should take paroxetine with food
- decreased sex drive or sexual problems, including difficulty maintaining an erection (staying hard) and difficulty reaching orgasm (coming)
Common side effects (affecting up to one in ten people) include:
- loss of appetite
- higher blood cholesterol (seen in blood tests)
- weight gain
- finding it difficult to concentrate
- feeling agitated
- insomnia (sleep problems), unusual dreams, or sleepiness
- dizziness and shaking
- headache
- dry mouth
- blurred vision
- feeling very weak
- diarrhoea (loose poo) or constipation (difficulty pooing)
- being sick
- sweating more than usual
- unusual yawning
Particular side effects that are more common in young people under 18 include:
- an increase in thoughts of harming themselves or taking their own lives
- deliberate self-harm
- being hostile, aggressive or unfriendly
- low appetite
- shaking
- excessive sweating
- hyperactivity (having too much energy)
- feeling agitated
- changing emotions and moods, including crying
There are other side effects that you can get when taking this medicine – we have only included the most common ones here.
Please look at the leaflet inside your medicine box, or ask a doctor or pharmacist, if you want to know whether you are getting a side effect from your medicine.
If you do get a side effect, please think about reporting it via the Yellow Card Scheme.
Body
A side effect of paroxetine can be not feeling as hungry as normal, which might lead to weight loss.
It is also possible to have a side effect of weight gain.
It is very difficult to know how it will affect each person who takes it.
Talk to your doctor about this if it worries you.
Sleep
You can feel sleepy in the first few days of taking paroxetine.
You can also have sleep problems (insomnia, vivid dreams).
These should, however, get better after the first week or two.
If you feel very sleepy, and you’ve been taking paroxetine for more than a month, you should go back to the doctor and see what else you can try.
Sex and fertility
Sex
Paroxetine can have side effects that might affect your sex life. These include:
- decreased libido (sex drive)
- difficulty getting an erection (getting hard) and ejaculating (coming)
- difficulty reaching orgasm (coming) the same way as before
More rarely, paroxetine can have the following side effects, which might affect your sex life:
- a painful erection that lasts for a long time (priapism). If this happens to you, visit a hospital or see your doctor immediately as this condition can be serious
- bleeding from the vagina, or irregular periods
- growth of the breasts and some milk flow, regardless of gender
These effects should pass after the first couple of weeks. If they do not, and this is a problem for you, go back to the doctor and see what else you could try.
The good effects of paroxetine may, after a while, have a positive impact on your sex life as your mood lifts and you become interested in life and relationships again.
Fertility
There have not been any reports of human fertility problems with paroxetine or other SSRI antidepressant medicines.
You should use good contraception when you are taking paroxetine. This is because there may be a slightly higher risk of heart problems in the developing baby if you take paroxetine in the early stages of pregnancy (see next section).
If you do become pregnant while you are on paroxetine, you should carry on taking the medicine and go back to your doctor as soon as possible to discuss whether you should stop or change your medicine.
Remember that you need to stay well through your pregnancy, and you may need a medicine to help you do that.
Pregnancy, post-natal and breastfeeding
Pregnancy
There may be a slightly higher risk of heart problems in the baby if you take paroxetine during the early stages of pregnancy.
If you and your doctor agree that you should carry on taking paroxetine during your pregnancy, you should tell your midwife that you are taking it at your first appointment.
Post-natal
If paroxetine is taken in the last five months of a pregnancy, it can cause a serious condition called persistent pulmonary hypertension of the new-born (PPHN). This can make the baby breathe faster and look a bit blue in colour. PPHN affects around three in 1,000 babies born to mums who take SSRIs. This compares with a rate of two in 1,000 among babies born to mums who do not take SSRIs.
PPHN appears in the first 24 hours after birth. You will need help from the midwife and doctors, so it is better if they are looking out for symptoms.
Your newborn baby may also develop withdrawal effects, including:
- shaking
- being sick
- not feeding properly
- being very tired
- being unable to sleep
- crying a lot
- being too hot or too cold
- having extra muscle reactions (reflexes)
- extra alertness
These might not appear straight away, so you should look out for them over the first few days after the baby is born.
Breastfeeding
Paroxetine is passed to the baby in breastmilk in small amounts and this can help with any withdrawal effects.
Talk to your doctor or midwife about your feeding options.
Driving and transport
Do not drive or ride a bike just after you start taking paroxetine.
Taking paroxetine may affect your ability to do things like driving a car, riding a bike, using machines, or anything else that needs a lot of focus.
You might find it difficult to concentrate, you might feel sleepy and your eyesight may be blurred.
It might be best to stop doing these things for the first few days, until you know how paroxetine affects you or until the effects pass.
You could get a friend or family member to go with you and see if they notice a difference in your driving.
Do not worry - most people drive as normal while taking paroxetine.
School and exams
Try not to take paroxetine for the first time just before your exams.
You might find it difficult to concentrate, you might have sleep problems and your eyesight may be blurred. You also might find it difficult to sit still.
You should talk to your doctor about any future exams if you are starting paroxetine.
You might decide together to delay starting it until you have done them. If they are more than a month away, however, you might find that it is better to start paroxetine to lift your mood and improve your motivation to study.
Do not worry - most people take exams as normal while taking paroxetine.
Friends and family
You may want to let your family and friends know you are taking paroxetine so they can support you and help you look out for side effects.
For guidance on this, check out our page on getting support with your medication.
Sport
Paroxetine is not a banned substance in sport.
Taking paroxetine may affect your ability to do things like riding a bike, competitive gymnastics, or anything else that needs a lot of focus.
You might find it difficult to concentrate, you might have sleep problems and your eyesight may be blurred. You may also find it difficult to sit still.
It might be best to stop such sports for the first few days, until you know how it affects you or the effects get better.
Do not worry - most people play sports as normal while taking paroxetine.
Alcohol and street drugs
Alcohol
You can continue to drink some alcohol while taking paroxetine.
Drinking alcohol every day, however, can make the symptoms of depression worse and you will not feel the benefit of your medicine.
The two together might make you sleepy or you might lose your focus when you first start taking paroxetine.
This could be dangerous if you drive or use machines or do anything that needs a lot of focus.
During the first few days, it might be best to stop drinking alcohol until you see how the medicine affects you, or until the effects pass.
Street drugs
We do not know how paroxetine mixes with street drugs, but it is likely to be similar to other SSRIs.
Cannabis can make drowsiness worse with paroxetine and give you a fast heartbeat.
Cannabis and other drugs may have their own side effects on your mental health, like anxiety or psychosis. For more information, have a look at our drugs and alcohol page.
Methadone can make drowsiness worse with paroxetine. The paroxetine is likely to increase the concentration of methadone in your body. There is also an increased risk of serotonin syndrome.
Paroxetine could raise the level of cocaine in your body, giving you a bigger reaction. There may be an increased chance of having a seizure (fit).
Taking paroxetine with cocaine, ecstasy or amfetamines could bring on serotonin syndrome. You could get a high temperature/fever, agitation, confusion, trembling or weird muscle movements. You need to go to hospital if this happens. Tell the doctor everything that you have taken.
Prescription medicines
Paroxetine does not mix well with some other medicines and drugs.
Do not take paroxetine if you take an antidepressant medicine called a monoamine oxidase inhibitor (MAOI), or if you have taken one in the last two weeks. MAOIs include moclobemide, isocarboxazid, phenelzine and tranylcypromine.
Talk to your doctor or pharmacist if you are taking any other medicines.
Tell the pharmacist you are taking paroxetine if you buy medicines over the counter (including things you put on your skin) for common illnesses.
References and further reading
For more helpful links and information, have a look at our references and further reading page.