Keep your regular appointments with your doctor. This is so your doctor can check on your progress.
Mianserin may make you feel sleepy. If this happens, do not drive and do not use tools or machines. Do not drink alcohol.
Tell your doctor if you experience any troublesome side-effects.
|Type of medicine||A tricyclic-related antidepressant|
Mianserin belongs to a group of medicines known as tricyclic-related antidepressants. It is prescribed for the treatment of depression. Depression can develop for no apparent reason, or it may be triggered by a life event such as a relationship problem, bereavement, or illness. People with depression have a consistently low mood and other symptoms severe enough to interfere with normal day-to-day activities.
Mianserin is thought to work by interfering with certain brain chemicals (called neurotransmitters) which may be involved in causing the symptoms of depression. It can be especially helpful if you are also having difficulty sleeping.
Before taking mianserin
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking mianserin it is important that your doctor knows:
- If you are pregnant or breastfeeding.
- If you have an overactive thyroid gland.
- If you have a problem with the way your liver works, or with the way your kidneys work.
- If you have epilepsy or diabetes (diabetes mellitus).
- If you have had problems with constipation.
- If you have any difficulties passing urine, or if you have had prostate trouble.
- If you have a heart disorder or blood vessel disease.
- If you have ever had a mental health problem (in particular, bipolar disorder or psychosis).
- If you have increased pressure in your eyes, a condition called glaucoma.
- If you have been told you have a tumour on your adrenal gland, called phaeochromocytoma.
- If you have a rare inherited blood disorder called porphyria.
- If you are taking any other medicines, including those available to buy without a prescription, as well as herbal and complementary medicines. This is especially important if you have recently taken a medicine for depression, known as a monoamine-oxidase inhibitor (MAOI).
- If you have ever had an allergic reaction to a medicine.
How to take mianserin
- Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about mianserin and will provide you with a full list of the side-effects which you may experience from taking it.
- It is usual to be prescribed a dose of 30-40 mg daily to begin with. Your doctor may ask you to take this divided into several doses during the day, or as a single dose taken at bedtime. The directions for taking it will be printed on the label of the pack of tablets to remind you what the doctor said to you. As your body gets used to the new medicine, your dose may be increased. If you have any questions at any time about what dose to take, ask your pharmacist for advice.
- Swallow mianserin tablets whole - do not crush, chew or break them. Many people find if helps to swallow the tablets with a drink of water. You can take mianserin before or after meals.
- If you forget to take a dose, take one as soon as you remember. If when you remember, it is nearly time for your next dose then leave out the missed dose and take your next dose when it is due. Do not take two doses together to make up for a forgotten dose.
Getting the most from your treatment
- Try to keep your regular appointments with your doctor. This is because your doctor will want you to have blood tests (especially during the first few months of treatment) and will want to check on your progress.
- You may feel that the tablets are not working for you straightaway. It can take a week or two for the effect to build up, and 4-6 weeks before you feel the full benefit. It is important that you do not stop taking the tablets thinking they are not helping. Also, while you feel depressed, you may have distressing thoughts, and think about harming yourself or ending your life. If this happens, it is very important that you tell your doctor about it straightaway.
- There are several types of antidepressants - each type works in a slightly different way and can have different side-effects. If you find that mianserin does not suit you, then let your doctor know, as another antidepressant may be found that does.
- Your doctor will recommend that you do not drink alcohol while you are on mianserin. This is because it increases the risk of side-effects, such as feeling sleepy.
- Some people who take mianserin find that their skin becomes more sensitive than usual to sunlight. Try to avoid strong sunlight until you know how your skin reacts, or use a sun cream with a high sun protection factor. Do not use sunbeds.
- If you buy any medicines, check with a pharmacist that they are suitable for you to take. This is because a number of medicines can increase the risk of side-effects from mianserin, including some strong painkillers, flu remedies and antihistamines which can be bought from pharmacies.
- If you have diabetes you may need to check your blood sugar (glucose) more frequently. This is because mianserin can alter the levels of sugar in your blood. Your doctor will advise you about this.
- If you are due to have any medical treatment, tell the person carrying out the treatment that you are taking mianserin, as it can interfere with some anaesthetics.
- Continue to take mianserin until your doctor tells you otherwise. Stopping treatment suddenly can sometimes cause problems and your doctor may want you to reduce your dose gradually when this becomes necessary. Your doctor may ask you to carry on taking mianserin even after you feel better. This is to help stop your symptoms from returning.
Can mianserin cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with mianserin. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.
|Common mianserin side-effects||What can I do if I experience this?|
|Feeling sleepy, blurred vision||Do not drive and do not use tools or machines until you feel better. Do not drink alcohol|
|Dry mouth||Try chewing sugar-free gum or sucking sugar-free sweets|
|Constipation||Try to eat a well-balanced diet containing plenty of fibre and drink plenty of water each day|
|Feeling sick (nausea), diarrhoea||Stick to simple meals - avoid rich or spicy foods. Drink plenty of water to replace lost fluids|
|Feeling dizzy or light-headed when getting up||Getting up more slowly may help. If you begin to feel faint, sit down and wait until the feeling passes|
|Other side-effects include feeling anxious or confused, sleeping problems, problems passing urine, tingling feelings, breast tenderness, problems when having sex, changes in appetite and weight, changes in the way things taste, ringing noise in the ears, itchy skin rash, hair loss, increased sweating, changes in heart rate or rhythm||If any of these become troublesome, speak with your doctor for advice|
Important: a few people taking mianserin have developed changes to some blood tests. Although your doctor will check for these, it is important that you let your doctor know as soon as possible if you develop any signs of an infection, such as a high temperature or a sore throat or mouth.
If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice.
How to store mianserin
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
Important information about all medicines
Never take more than the prescribed dose. Tricyclic antidepressants can be dangerous in overdose. If you suspect that you or someone else might have taken an overdose, go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.
This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about this medicine ask your pharmacist.
Further reading and references
Manufacturer's PIL, Mianserin 30 mg film-coated tablets; Mylan Products Ltd, The electronic Medicines Compendium. Dated December 2013.
British National Formulary, 80th Edition (Sep 2020); British Medical Association and Royal Pharmaceutical Society of Great Britain, London.