Consumer medicine information



Active ingredient(s): Desvenlafaxine Succinate

Consumer Medicine Information (CMI)

This leaflet provides important information about using PRISTIQ. You should also speak to your doctor or pharmacist if you would like further information or if you have any concerns or questions about using PRISTIQ.

Where to find information in this leaflet:

1. Why am I using PRISTIQ?
2. What should I know before I use PRISTIQ?
3. What if I am taking other medicines?
4. How do I take PRISTIQ?
5. What should I know while using PRISTIQ?
6. Are there any side effects?
7. Product details

1. Why am I using PRISTIQ?

PRISTIQ contains the active ingredient desvenlafaxine succinate. It belongs to a class of medications called Serotonin-Noradrenaline Reuptake Inhibitors (SNRIs).

Serotonin and noradrenaline are chemical messengers that allow certain nerves in the brain to work. PRISTIQ tablets increase the level of these two messengers. Experts think this is how it helps to restore your feeling of wellness.

PRISTIQ is used in the treatment and prevention of relapse of depression.

Depression can affect your whole body and may cause emotional and physical symptoms such as feeling low in spirit, being unable to enjoy life, poor appetite or overeating, disturbed sleep, loss of sex drive, lack of energy and feeling guilty over nothing.

Ask your doctor if you have any questions about why PRISTIQ has been prescribed for you.

Your doctor may have prescribed it for another reason.

2. What should I know before I use PRISTIQ?


Do not use PRISTIQ if:

  1. You are allergic to desvenlafaxine, venlafaxine, or any of the ingredients listed at the end of this leaflet.
  2. Always check the ingredients to make sure you can use this medicine.
  3. You are taking other medications for depression known as monoamine oxidase inhibitors, even if you have stopped taking them, but have taken them within the last 14 days.

Check with your doctor if you have:

  • Other medications that you are taking
  • A history of fits (seizures or convulsions)
  • A personal history or family history of bipolar disorder
  • Blood pressure problems
  • Glaucoma (increased pressure in the eye)
  • A tendency to bleed more than normal or you are taking a blood thinning medication
  • Raised cholesterol or lipid levels
  • Problems with your kidneys or liver
  • Problems with your heart
  • Low sodium levels in your blood
  • Any other medical conditions.

During treatment, you may be at risk of developing certain side effects. It is important you understand these risks and how to monitor for them. See additional information under Section 6. Are there any side effects?

Pregnancy and breastfeeding

Check with your doctor if you are pregnant or intend to become pregnant.

Talk to your doctor if you are breastfeeding or intend to breastfeed.

PRISTIQ is not recommended for use during pregnancy. Your doctor will discuss the risks and benefits of taking PRISTIQ if you are pregnant. One of these risks is that newborn babies whose mothers have been taking PRISTIQ may have several problems including breathing difficulties, rapid breathing, seizures, lack of oxygen in their blood, physical and / or behavioural problems, vomiting and diarrhoea.

If you take PRISTIQ or similar anti-depressants mid to late in your pregnancy, you may develop a condition known as “pre-eclampsia”, which is characterised by persistent high-blood pressure during or after pregnancy. Symptoms of pre-eclampsia can include headaches, abdominal pain, shortness of breath or burning behind the sternum, nausea and vomiting, confusion, heightened state of anxiety, and/or visual disturbances such as oversensitivity to light, blurred vision, or seeing flashing spots or auras.

If you take PRISTIQ or similar antidepressants in the last month of your pregnancy, you may experience heavy bleeding during and/or after delivery.

Continuing treatment with PRISTIQ or similar antidepressants during pregnancy should be strictly as directed by your doctor. Symptoms of a relapse may occur if treatment is discontinued, even if major depression was previously under control.

Tell your doctor or pharmacist if you are breast-feeding or plan to breast-feed.

PRISTIQ passes into breast milk and there is a possibility that the breast-fed baby may be affected. For this reason, the use of PRISTIQ is not recommended in breast-feeding women.

3. What if I am taking other medicines?

Tell your doctor or pharmacist if you are taking any other medicines, including any medicines, vitamins or supplements that you buy without a prescription from your pharmacy, supermarket or health food shop such as St John’s wort or tryptophan supplements.

Do not start to take any other medicine while you are taking PRISTIQ, unless it is prescribed or approved by your doctor.

Some medicines may interfere with PRISTIQ and affect how it works. These include:

  • Medications for depression known as monoamine oxidase inhibitors (such as moclobemide, phenelzine and tranylcypromine). Tell your doctor if you are taking or have stopped taking them within the last 14 days. Ask your doctor or pharmacist if you are unsure if you are taking any of these medicines. It is important that you do not take PRISTIQ or medicines similar to PRISTIQ with monoamine oxidase inhibitors or within 14 days of taking a monoamine oxidase inhibitor as this may result in a serious life-threatening condition. Your doctor or pharmacist can tell you what to do if you are taking any of these medicines.
  • Any other medications for bipolar disorder, depression, anxiety, obsessive-compulsive disorder or pre-menstrual dysphoric disorder, including St John’s wort
  • Drugs that affect serotonin levels e.g. tramadol, dextromethorphan, fentanyl, methadone and pentazocine
  • Medicines used to treat Attention Deficit Hyperactivity Disorder (ADHD) such as dexamphetamine and lisdexamphetamine
  • Medicines for weight loss, including sibutramine
  • Triptans (used to treat migraine)
  • Linezolid (used to treat infections)
  • Drugs that affect your tendency to bleed (e.g. Aspirin, NSAIDS, Warfarin)
  • Opioids (used to manage pain)

You may need to take different amounts of your medicine, or you may need to take different medicines. Your doctor will advise you.

Your doctor or pharmacist has more information on medicines to be careful with or to avoid while taking PRISTIQ.

Check with your doctor or pharmacist if you are not sure about what medicines, vitamins or supplements you are taking and if these affect PRISTIQ.

4. How do I take PRISTIQ?

How much to take

The usual dose is 50 mg taken once daily with or without food.

Swallow tablets whole with a glass of water or other non-alcoholic liquid.

Do not divide, crush, chew or place the tablets in water.

Do not change your dose unless your doctor tells you to.
Your doctor will gradually increase your dose if needed.

If you have kidney problems, you may need a lower dose of PRISTIQ.

Follow the instructions provided and use PRISTIQ until your doctor tells you to stop.

Do not be concerned if you see a tablet ‘shell’ in your faeces after taking PRISTIQ.

As the tablet travels the length of your gastrointestinal tract, the active ingredient desvenlafaxine is slowly released. The tablet ‘shell’ remains undissolved and is eliminated in your faeces. Therefore, even though, you may see a tablet ‘shell’ in your faeces, your dose of desvenlafaxine has been absorbed.

How long to take PRISTIQ

Continue taking your medicine for as long as your doctor tells you.

Although you may begin to feel better after two weeks, it may take several weeks before you feel much better. It is important to give PRISTIQ time to work.

This medicine helps to control your condition, so it is important to keep taking your medicine even if you feel well.

When to take PRISTIQ

Take PRISTIQ at approximately the same time each day.

This could be either in the morning or in the evening.

Taking it at the same time each day will have the best effect. It will also help you remember when to take it.

If you forget to use PRISTIQ

PRISTIQ should be used regularly at the same time each day.

If you miss your dose and if it is less than 12 hours until your next dose, skip the dose you missed and take your next dose when you are meant to. Otherwise, take it as soon as you remember, and then go back to taking as you would normally.

Do not take a double dose to make up for the dose you missed. This may increase the chance of you getting an unwanted side effect.

If you are not sure what to do, ask your doctor or pharmacist.

If you have trouble remembering when to take your medicine, ask your pharmacist for some hints.

If you use too much PRISTIQ

If you think that you have used too much PRISTIQ, you may need urgent medical attention.

You should immediately:

  • Phone the Poisons Information Centre
    (by calling 13 11 26), or
  • Contact your doctor, or
  • Go to the Emergency Department at your nearest hospital.

You should do this even if there are no signs of discomfort or poisoning.

5. What should I know while using PRISTIQ?

Things you should do

Visit your doctor regularly for a checkup so that your progress can be checked. Always discuss any questions you have about PRISTIQ with your doctor.

Take PRISTIQ tablets as your doctor has prescribed.

Tell any other doctors, dentists and pharmacists who treat you that you are taking this medicine.

Keep enough PRISTIQ tablets to last weekends and holidays.

This medicine helps to control your condition but does not cure it. It is important to keep taking your medicine even if you feel well.

Watch carefully for signs that your depression is getting worse, especially in the first few weeks of treatment or if your dose has changed.

Sometimes people with depression can experience a worsening of their depressive symptoms. This can happen even when taking an antidepressant.

Tell your doctor there is the potential for a false positive urinary drug screen while on PRISTIQ.

Call your doctor immediately if you experience any of the following symptoms, especially if they are severe, you have not had these symptoms before or they happen very suddenly:

  • Anxiety or agitation
  • Panic attacks
  • Difficulty sleeping
  • Irritability
  • Confusion
  • Hallucination (seeing or hearing things)
  • Aggressiveness
  • Hostility or impulsiveness
  • Restlessness
  • Unusual/involuntary muscle movements (e.g., hyper-reflex or blurred vision)
  • Irregular/high blood pressure, irregular/increased heart rate and/or fever
  • Overactivity or uninhibited behaviour
  • Other unusual changes in behaviour
  • Worsening depression
  • Thoughts of suicide.

High fever, stiffness of the muscles, altered mental status (paranoid behaviour) and autonomic dysfunction (wide swings of blood pressure, excessive sweating and excessive saliva) may be signs of something called neuroleptic malignant syndrome.

Headache, shivering, diarrhoea, muscle stiffness, high fever and seizures may be signs of something called serotonin syndrome.

Neuroleptic malignant syndrome and serotonin syndrome are serious and may be life-threatening. Symptoms of neuroleptic malignant syndrome or serotonin syndrome can vary, if you think you might have either of these syndromes while taking PRISTIQ, call your doctor immediately or go to the emergency department of nearest hospital. If you have severe or rapidly worsening symptoms, seek emergency treatment immediately.

Tell your doctor immediately if you have any thoughts about suicide or doing harm to yourself.

Warning signs of suicide:

If you or someone you know is showing the following warning signs, contact your doctor or a mental health advisor right away or go to the nearest hospital for treatment.

All thoughts or talk about suicide or violence are serious.

  • Thoughts or talk about death or suicide
  • Thoughts or talk about self-harm or doing harm to others
  • Any recent attempts of self-harm
  • An increase in aggressive behaviour, irritability or agitation.

Things you should not do

Do not stop using this medicine or change the dose without the advice of your doctor, even if you feel better.

Your doctor may want to slowly decrease your dose of PRISTIQ to help avoid side effects. Side effects are known to occur when people stop taking PRISTIQ, especially when they suddenly stop therapy.

Some of these side effects include:

  • Headache
  • Nausea
  • Dizziness
  • Tiredness
  • Irritability
  • Anxiety
  • Abnormal dreams
  • Diarrhoea
  • Excessive sweating
  • Visual impairment
  • High blood pressure

Slowly reducing the amount of PRISTIQ being taken reduces the possibility of these effects occurring. In some people this may need to occur over periods of months or longer.

Some of these symptoms may impair driving, or the operation of dangerous machinery. Avoid these activities if you experience any of these symptoms.

Do not give this medicine to anyone else even if they have the same condition as you.

Driving or using machines

Be careful before you drive or use any machines or tools until you know how PRISTIQ affects you.

PRISTIQ may cause dizziness in some people.

Drinking alcohol

Tell your doctor if you drink alcohol.

Avoid drinking alcohol while you are taking PRISTIQ.

Looking after your medicine

Keep your PRISTIQ tablets in their blister pack until it is time to take them.

The tablets may not last as well if you take them out of the blister pack.

Store it in a cool (below 25°C) dry place away from moisture, heat or sunlight; for example, do not store it:

  • in the bathroom or near a sink, or
  • in the car or on window sills.

Heat and dampness can destroy some medicines.

Keep PRISTIQ tablets and all medication where young children cannot reach it.

A locked cupboard, at least one-and-a-half metres above the ground, is a good place to store medicines.

Do not use this medicine after the expiry date.

Keep it where young children cannot reach it.

Getting rid of any unwanted medicine

If your doctor tells you to stop taking this medicine or the expiry date has passed, ask your pharmacist what to do with any medicine that is left over.

6. Are there any side effects?

All medicines can have side effects. If you do experience any side effects, most of them are minor and temporary. However, some side effects may need medical attention.

See the information below and, if you need to, ask your doctor or pharmacist if you have any further questions about side effects.

Side effects

Side effects What to do
  • Stomach, bowel or urinary tract problems:
    – Nausea or vomiting
    – Loss of appetite
    – Diarrhoea
    – Constipation
    – Difficulty passing urine
  • Changes in your behaviour:
    – Difficulty sleeping, abnormal sleepiness or abnormal dreams
    – Sexual function problems such as decreased sex drive, delayed ejaculation, problems achieving erection or difficulties achieving orgasm
    – Nervousness or anxiety
    – Feeling jittery or irritable
  • Difficulty thinking or working because of:
    – Yawning
    – Disturbances in concentration
    – Fainting or dizziness after standing up
    – Fatigue
    – Rapid heartbeat
    – Chills
    – Headache
  • Excessive sweating
  • Hot flushes
  • Rash
  • Weight loss
  • Weight gain
  • Blurred vision
  • Ringing in the ears
  • Altered taste, dry mouth.
Speak to your doctor if you have any of these less serious side effects and they worry you.

Serious side effects

Serious side effects What to do
  • Muscle spasms, stiffness, weakness or movement disorders
  • Abnormal facial movements such as tongue thrusting, repetitive chewing, jaw swinging, or grimacing
  • A feeling of apathy or not caring about things
  • Feeling detached from yourself
  • Hallucinations
  • Confusion
  • Agitation
  • Unusually overactive
  • Problems with breathing, shortness of breath
  • Bleeding or bruising more easily than normal
  • Numbness or pins and needles
  • Sensitivity to sunlight.
Call your doctor as soon as possible.
  • Palpitations, shortness of breath, intense chest pain, or irregular heartbeats
  • Severe upper abdominal pain
  • Swollen and tender abdomen
  • Fever
  • Rise or decrease in blood pressure. You may experience headache, blurred vision, palpitations, confusion or loss of consciousness. Sometimes you may not experience any of these symptoms. It is important to keep your routine doctor’s appointments so that your blood pressure can be checked
  • Swelling of the face, lips, tongue, throat or other parts of the body
  • Seizures or fits
  • Symptoms of sudden fever with sweating, rapid heartbeat and muscle stiffness, which may lead to loss of consciousness.
Call your doctor straight away, or go straight to the Emergency Department at your nearest hospital if you notice any of these serious side effects.

Tell your doctor or pharmacist if you notice anything else that may be making you feel unwell.

Other side effects not listed here may occur in some people.

Some of these side effects (for example, increase in blood pressure, increase in blood cholesterol, changes to liver function, protein in the urine) can only be found when your doctor does tests from time to time to check your progress.

This is not a complete list of all possible side effects. Others may occur in some people and there may be some side effects not yet known.

Tell your doctor if you notice anything that is making you feel unwell.

Reporting side effects

After you have received medical advice for any side effects you experience, you can report side effects to the Therapeutic Goods Administration online at By reporting side effects, you can help provide more information on the safety of this medicine.

Always make sure you speak to your doctor or pharmacist before you decide to stop taking any of your medicines.

7. Product details

This medicine is only available with a doctor’s prescription.

What PRISTIQ contains

Active ingredient
(main ingredient)
50 mg or 100 mg desvenlafaxine succinate
Other ingredients
(inactive ingredients)
Microcrystalline cellulose
Purified talc
Magnesium stearate
Polyvinyl alcohol
Titanium dioxide
Iron oxide red
Iron oxide yellow (50 mg tablet only)
Sunset yellow FCF CI15985 (100 mg tablet only).

Do not take this medicine if you are allergic to any of these ingredients.

PRISTIQ does not contain gluten

What PRISTIQ looks like

There are two strengths of PRISTIQ tablets:

The 50 mg tablet is light pink, square (pyramid, one sided) film coated tablet debossed with “W” over “50” on the flat side. (Aust R 170674)

The 100 mg tablet is a reddish-orange, square (pyramid, one sided) film coated tablet debossed with “W” over “100” on the flat side. (Aust R 170696)

Each blister pack contains 28 tablets.

Who distributes PRISTIQ

Pfizer Australia Pty Ltd
Sydney NSW
Toll Free Number: 1800 675 229

This leaflet was prepared in September 2022.