Paroxetine

Sounds like 'pa-rox-e-teen'

Easy-to-read medicine information about paroxetine – what it is, how to take paroxetine safely and possible side effects.

Type of medicine Also called
  • Antidepressant
  • Belongs to a group of medicines known as selective serotonin re-uptake inhibitors (SSRIs)
  • Apo-Paroxetine®
  • Aropax®

What is paroxetine?

Paroxetine is a medicine used to treat depression, obsessive compulsive disorderpanic attacks and post traumatic stress disorder (PTSD).  It belongs to a group of medicines called selective serotonin reuptake inhibitors (SSRIs). It is believed that SSRIs work by increasing the activity of certain chemicals working in our brains called neurotransmitters. These pass signals from one brain cell to another. Although we don’t know for certain, the neurotransmitters that are most likely to be involved in depression and some other conditions are thought to be serotonin and noradrenaline. Selective serotonin reuptake inhibitors (SSRIs) are the most frequently prescribed antidepressants. SSRIs are called selective because they only affect serotonin. In New Zealand paroxetine is available as tablets. 

Read more about antidepressants and SSRIs.

Dose

  • The dose of paroxetine will be different for different people. Your doctor will usually start you on a low dose and if you need to, will increase your dose slowly. This allows your body to get used to the medicine and reduces side effects.
  • Always take your paroxetine exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much paroxetine to take, how often to take it, and any special instructions. 

How to take paroxetine

  • Take paroxetine once a day, in the morning, after breakfast. Take your dose at the same time each day. It is best to take paroxetine with food.
  • If you forget to take your dose, take it as soon as you remember. But, if it is nearly time for your next, just take the next dose at the right time. Do not take double the dose.
  • Keep taking paroxetine every day. It may take 4 to 6 weeks before you notice the full benefits of paroxetine.
  • If you think paroxetine is not working for you, do not stop taking it suddenly; speak to your doctor or nurse before stopping. It is important to stop taking paroxetine very slowly, over a few weeks to avoid side effects.

Read more about what to expect when starting SSRIs – see SSRIs and frequently asked questions (FAQs) about SSRIs.

Precautions – before starting paroxetine

  • Do you have any heart problems such as irregular heartbeat?
  • Have you had problems with mania or psychosis?
  • Do you have problems with your kidneys or liver?
  • Do you have epilepsy?
  • Do you have diabetes? 
  • Are you pregnant or breastfeeding?
  • Do you have a bleeding disorder or stomach ulcer?
  • Are you taking any other medicines, including medicines you can buy without a prescription, such as herbal and complementary medicines or pain relief medicines?

If any of these apply, it’s important that you tell your doctor or pharmacist before you start paroxetine. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

Precautions – while taking paroxetine

  • Alcohol:  avoid alcohol while you are taking paroxetine, especially when you first start treatment. Drinking alcohol while taking SSRIs can cause drowsiness and affect concentration, putting you at risk of falls and other accidents. It can also cause agitation, aggression and forgetfulness. If you do drink alcohol, drink only small amounts and see how you feel. Do not stop taking your medication.
  • Diabetes: if you have diabetes, you may need to check your blood glucose more often because paroxetine can affect the levels of glucose in your blood. 

Possible side effects

Like all medicines, paroxetine can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Suicidal behaviour

The use of antidepressants has been linked with an increase in suicidal thoughts and behaviour. Children, teenagers, young adults and people with a history of suicidal behaviour are particularly at risk. This is most likely during the first few weeks of starting an antidepressant or if the dose is changed. It is important to look for signs of suicidal behaviour such as agitation or aggression and ask about suicidal thoughts, self-harm, worsening of low mood, If you notice any of these signs, contact your doctor immediately.
It is ok and important to ask about suicidal thoughts and this will not increase risk. Note: paroxetine is not usually prescribed to people under 18 years of age.

If you need urgent help or are concerned, phone:

  • Lifeline 0800 543 354 (available 24/7), or
  • Healthline 0800 611 116, who can give you the phone number for your local mental health crisis line.

Risk of bleeding

SSRIs can increase your risk of bleeding especially if taken with NSAIDs (non-steroidal anti-inflammatory drugs) such as diclofenac and ibuprofen. Check with your doctor or pharmacist before you take pain relief.

Sexual side effects

SSRIs in both men and women can cause reduced sexual drive, lack of libido and problems keeping an erection and reduce the intensity of orgasm. It’s important to talk to your healthcare provider if you get these effects, as they can be difficult to deal with and may not go away. Your healthcare provider may be able to suggest treatment or may reduce the dose of the SSRI or change to a different one.

Other side effects

Side effects What should I do?
  • Nausea (feeling sick)
  • This is quite common when you first start paroxetine
  • Try taking your dose with food
  • Difficulty falling asleep
  • Take paroxetine in the morning
  • Feeling sleepy, drowsy, dizzy or tired
  • Be careful when driving or using tools until you know how this medicine affects you
  • Tell your doctor if troublesome
  • Dry mouth
  • Increased sweating
  • Tremor
 
  • These are quite common when you first start taking paroxetine and may go away with time
  • Tell your doctor if troublesome
  • Changes in appetite
  • Changes in weight
  • Tell your doctor
  • It may be helpful to make changes to your diet and usual exercise
  • Loss of sex drive or libido
  • Tell your doctor
  • Suicidal thoughts, thoughts of harming yourself, or worsening depression
  • Tell your doctor immediately or ring HealthLine 0800 611 116
  • Changes in heartbeat such as fast heart rate or irregular heartbeat  
  • Tell your doctor immediately or ring HealthLine 0800 611 116
  • Signs of serotonin syndrome such as feeling agitated and restless, heavy sweating, shivering, fast heart rate or irregular heartbeat, headache, diarrhoea and rigid or twitching muscles 
  • You are at increased risk of serotonin syndrome if you just started taking paroxetine or  increased the dose or started other medicines that can cause serotonin syndrome 
  • Tell your doctor immediately or ring HealthLine 0800 611 116

Interactions

Paroxetine interacts with many other medications (including pain relief medicines) and herbal supplements (such as St. John's Wort) so check with your doctor or pharmacist before starting paroxetine or before starting any new medicines.

Learn more

The following links have more information on paroxetine.

Medsafe Consumer Information Sheets: Aropax 
New Zealand Formulary Patient Information: paroxetine

References

  1. Paroxetine New Zealand Formulary
  2. Selective serotonin re-uptake inhibitors New Zealand Formulary
  3. The role of medicines in the management of depression in primary care BPAC, 2017
Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 16 Feb 2018