Mirtazapine - oral


Patient Medicine Information
Why do I need this medicine?
Mirtazapine is used to treat depression.
How do I take this medicine?
Take Mirtazapine exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

You may take this medicine with or without food. Try to take it at the same time each day.

Mirtazapine is available as a tablet, orodispersible tablet (orally disintegrating tablet) or an oral solution.

If you are taking the conventional tablet, swallow it whole. Do not divide, chew or crush the tablet.

If you are taking the orodispersible tablet:
  1. Remove it from the foil only just before you take it. Do not leave the orodispersible tablet exposed to air. Do not push the orodispersible tablet through the foil as it is fragile and easily broken.
  2. Remove the orodispersible tablet with dry hands by peeling the backing off the foil and tipping the tablet onto your dry hands. 
  3. Place the orodispersible tablet directly on your tongue as soon as it is taken out of the foil. The orodispersible tablet will immediately start to melt on the tongue. It can then be swallowed with or without water. 
Do not cut, break or crush the orodispersible tablets.

If you are taking the oral solution, follow these instructions:
  1. Remove the safety cap of the bottle and insert the syringe adapter in the bottle. 
  2. With the plunger fully depressed, insert the syringe into the opening of the adapter. 
  3. Invert the bottle upside down then pull the plunger to withdraw the exact amount of Mirtazapine as prescribed. If bubbles form, empty the syringe back into the bottle and repeat the withdrawal procedure.
  4. Empty the contents of the syringe into your mouth or onto a spoon or small glass of water. Stir well and drink immediately at once.
  5. Rinse the syringe with water and let it dry before its next use.
Mirtazapine must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed otherwise, as stopping it suddenly could worsen your condition.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double a dose under any circumstances.

If you often forget to take your medicine, let your doctor and pharmacist know.
When should I not use this medicine?
Do not take Mirtazapine if you are currently taking or have taken a medicine that is used to treat depression known as a monoamine oxidase inhibitor (MAOI) such as isocarboxazid, phenelzine, tranylcypromine, linezolid and intravenous (given into the vein) methylene blue in the last 14 days.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:
  • bipolar disorder (mood changes between feeling very high and very low)
  • existing or history of seizures
  • prostate enlargement or problems passing urine
  • diabetes
  • heart disease 
  • disease of the blood vessels supplying the brain
  • low blood pressure
  • increased pressure inside the eye
  • dehydration
  • kidney disease
  • liver disease
Let your doctor know if you are pregnant or breastfeeding.

Medicines for depression such as Mirtazapine may increase the risk of suicidal thoughts and behaviour. As depression and some psychiatric disorders are themselves associated with an increased risk of suicide, it is important for you or your family members to monitor your condition especially at the start of treatment and if your dosage is still being adjusted. If you experience new or sudden changes in mood, behaviour, thoughts or feelings or a worsening of your depression with suicidal thoughts or attempts, harm to self or harm to others, contact your doctor immediately.

Why is it important to keep my appointments with the doctor?

Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly. Routine tests (e.g. liver, kidney and heart function, cholesterol, sugar and electrolyte levels, blood tests and eye examination) may be done while you are being treated with this medicine. Regular monitoring of blood pressure may also be needed. Your doctor will advise you about how often you need to have these tests.

What lifestyle changes should I make to cope with depression?

Regular exercise and eating a healthy diet will help increase energy and hormones in the body such as serotonin, endorphins and other feel-good chemicals that minimise mood swings. Get enough sleep, as lack of sleep may cause irritability, moodiness, sadness, and tiredness.
What side effects could I experience?
Mirtazapine may cause you to suddenly fall asleep during your daily activities such as eating and watching television. Do not drive or take part in any activity in which you need to be alert.

Other side effects include any of the following: abdominal pain, anxiety, chest pain, confusion, constipation, cough, dehydration, difficulty in hearing, difficulty in sleeping, dry mouth, fever, irregular heartbeat, muscle pain, nausea, vomiting, increased appetite, menstrual problems, muscle rigidity, rash, shortness of breath, tremors, weakness, weight gain and swelling of ankles, feet or hand.,

This medicine may cause your blood pressure to fall suddenly when you get up from a sitting or lying down position and you may feel giddy. To minimise this problem, stand up slowly.

Mirtazapine may also cause the level of your red blood cells, white blood cells and platelets to drop.

Red blood cells carry oxygen around your body. A fall in the level of red blood cells may make you feel tired and worn out.

White blood cells help your body to fight infections. A fall in the level of your white blood cells may put you at higher risk for infections, such as coughs, colds and flu, which may lead to more serious infections. Avoid crowded places and people who are sick. Inform your doctor if you have a fever, or a cough or flu that does not go away.

Platelets help your blood to clot when there is a cut in the skin. A fall in the level of your platelets may put you at risk of bleeding more than usual. Do not take part in activities where you may fall or get injured, such as contact sports. Inform your doctor if you get any unusual bruising (large bruises or several bruises, especially if the bruises appeared on their own) or bleeding that takes a long time to stop (for example, too much bleeding when you floss or brush your teeth).

Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
  • rashes with peeling of the skin or blistering of the lips, mouth or eyes accompanied by fever
  • confusion and hallucinations (seeing, hearing or feeling things that are not existent)
  • unpleasant or distressing restlessness and need to move often with an inability to sit or stand still, severe incoordination of muscle and rigidity, high blood pressure, rapid heartbeat and prolonged diarrhoea 
  • unusual changes in mood or behaviour (being too depressed, agitated, or having thoughts of self-harm)
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Do not take Mirtazapine if you are currently taking or have taken a medicine that is used to treat depression known as a monoamine oxidase inhibitor (MAOI) such as isocarboxazid, phenelzine, tranylcypromine, linezolid and intravenous (given into the vein) methylene blue in the last 14 days.

Inform your doctor and pharmacist if you are taking any of these medicines:
  • medicines for mood disorders e.g. nefazodone, venlafaxine, fluoxetine, clomipramine
  • medicines to treat fungal infections e.g. ketoconazole, fluconazole
  • medicines to treat HIV infection e.g. ritonavir
  • medicines for moderate to severe pain e.g. tramadol
  • medicines for fits or seizure e.g. carbamazepine, phenytoin
  • medicines for high blood pressure e.g. clonidine, methyldopa
  • medicines to treat migraine e.g. sumatriptan, zolmitriptan
  • certain antibiotics e.g. erythromycin, azithromycin 
  • cimetidine (medicine used to reduce stomach acid production)
  • warfarin (blood-thinning medicine)
  • St. John’s Wort (herbal medicine)
This list does not include all medicines that may interact with Mirtazapine

Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

The orodispersible tablet must be kept in its original foil wrapper and original container. Do not store the orodispersible tablets in any other container except its original.

The oral solution should be used within 6 weeks after opening.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on mirtazapine - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2020 MIMS. All rights reserved. Powered by MIMS.com
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