Venlafaxine

Venlafaxine can be used to treat mental health conditions like depression, and sometimes anxiety and panic attacks.

Venlafaxine is usually taken once or twice a day with food. Follow the instructions that come with your medicine.

Common side effects of venlafaxine include feeling sick, headaches and diarrhoea. More serious side effects are rare.

Most adults can take venlafaxine, but always check before taking it as it's not suitable for everyone.

Taking venlafaxine with other medicines, such as some anticoagulants and anti-inflammatories, can cause problems. Always check before taking it.

Venlafaxine can be used to treat mental health conditions. It's mainly used to treat depression, but is sometimes used to treat anxiety, panic attacks and menopause symptoms such as hot flushes in women with breast cancer.

It's a type of antidepressant called a selective noradrenaline reuptake inhibitor (SNRI).

SNRIs are thought to work by increasing the level of serotonin and noradrenaline (chemicals in the brain that control mood). When the levels are normal, this may reduce stress levels and negative thoughts.

Venlafaxine usually comes as tablets or capsules that you swallow. How much you need to take and how you take it depends on why you're taking it and what type you're taking.

Your doctor may prescribe a low dose to start with and increase it after 2 to 3 weeks. This reduces the chances of side effects.

If your symptoms do not improve after taking venlafaxine for a while, your doctor may increase your dose further.

When taking venlafaxine:

• check the packet or leaflet to see if your tablets or capsules are "slow-release" (prolonged release)
• take slow-release tablets or capsules once a day – ideally at the same time each day
• take other venlafaxine tablets or capsules twice a day – ideally once in the morning and once in the evening
• swallow tablets and capsules whole with water
• take it with food

You may need to take venlafaxine for a long time. For example, if you're taking it for depression, you'll probably need to continue to take it for several months or more.

Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or have any problems taking it.

If you miss a dose of venlafaxine

If you forget to take venlafaxine, take it as soon as you remember.

If it's nearly time for your next dose, skip the missed dose and take your next dose at the usual time.

Do not take 2 doses to make up for a missed dose.

If you take too much venlafaxine

Taking an extra dose of venlafaxine can be dangerous.

• you've taken more than your prescribed dose of venlafaxine

If you're told to go to A&E, do not drive. Ask someone to drive you or call 999 and ask for an ambulance.

Bring the venlafaxine packet or leaflet inside it, any remaining medicine, and any other medicines you take.

Your doctor may suggest that you stop taking venlafaxine if you've been feeling better for some time.

But do not suddenly stop taking it because it may cause withdrawal symptoms. If you want to stop taking venlafaxine, speak to your doctor first.

Your doctor will gradually reduce your dose over several weeks or months. Always follow your doctor's advice.

Like all medicines, venlafaxine can cause side effects, although not everyone gets them.

Most side effects should ease after a couple of weeks as your body gets used to the medicine, but some can last longer.

Common side effects

Common side effects of venlafaxine include:

• headaches
• feeling sick (nausea) and being sick (vomiting)
• feeling dizzy or drowsy (sleepy)
• dry mouth
• diarrhoea or constipation
• sexual problems, such as low sex drive (loss of libido)
• problems sleeping (insomnia)
• weight changes

If you feel dizzy or drowsy after taking venlafaxine, do not drive, ride a bike or use machinery until these symptoms have gone away.

• you have any side effects that bother you or do not go away

They may be able to give you advice about how to reduce any side effects. Keep taking your medicine unless you're advised to stop.

Venlafaxine can sometimes cause more serious side effects, although most of them are rare.

Possible serious side effects of venlafaxine include:

• an allergic reaction (anaphylaxis) – causing symptoms such as a swollen throat or tongue, a raised, itchy rash and difficulty breathing
• serotonin syndrome – a condition that causes a fast heartbeat, sweating, shaking, twitching muscles and feeling confused or agitated
• very low mood and having suicidal thoughts
• unexplained muscle pain or weakness

• you're taking venlafaxine and think you might be having serious side effects
• you're having thoughts about harming yourself

Most adults can take venlafaxine.

But venlafaxine is not suitable for everyone. For example, it may not be suitable if:

• you've ever had an allergic reaction to venlafaxine or another SNRI antidepressant
• you have diabetes
• you have epilepsy
• you have heart disease
• you have glaucoma
• you have a bleeding disorder (particularly bleeding in the digestive system)
• you've ever had mania (high moods caused by a mental health condition), or someone in your family has

Before taking venlafaxine, tell your doctor if you have any other medical conditions.

Breastfeeding and venlafaxine

Tell your doctor if you're breastfeeding.

Venlafaxine is sometimes used while breastfeeding, but it's best to check because the medicine can pass into your breast milk.

You may be able to take it, if the benefits outweigh the risks. Sometimes your doctor might want to switch you to a different type of antidepressant.

It's possible for breastfed babies to get side effects from venlafaxine, so speak to a healthcare professional or call NHS 111 if you have any concerns about your baby.

Pregnancy and venlafaxine

Tell your doctor if you're pregnant or you get pregnant while taking venlafaxine.

Venlafaxine can be used during pregnancy if needed. Your doctor will talk to you about the risks and benefits of taking it while you're pregnant.

If you need to take venlafaxine while you're pregnant, your doctor will prescribe the lowest possible effective dose.

You may be advised to give birth in hospital so you and your baby can be closely monitored after you've given birth.

There are some medicines, herbal remedies and supplements that may not mix well with venlafaxine.

These include:

• anticoagulants, such as warfarin and apixaban
• non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen
• other antidepressants called monoamine oxidase inhibitors (MAOIs), such as moclobemide and selegiline

Do not use the herbal supplement St John's wort when taking venlafaxine.

Before taking venlafaxine, tell your doctor if you're taking any other medicines, herbal remedies, vitamins or supplements.

Food, drink and alcohol with venlafaxine

You can eat and drink normally when taking venlaxafine, but it's best not to drink alcohol because it can increase the risk of side effects.