How agomelatine works
Agomelatine helps against depression and anxiety. It also makes it easier to fall asleep.
Agomelatine inhibits the receptors of the body’s own messenger substance serotonin, the so-called 5HT2 receptors. As a result, the body releases more of the neurotransmitters dopamine and norepinephrine in the brain. In this way, the active ingredient can improve a disturbed dopamine and norepinephrine metabolism in the brain, which may be partly responsible for depressive disorders.
Agomelatine has a similar structure to the endogenous hormone melatonin and can therefore dock onto its binding sites (MT1 and MT2 receptors). Compared to melatonin, however, agomelatine is more stable. Thus, it acts longer at the binding sites than the hormone itself:
It is important that patients take the drug regularly for a sufficiently long period of time to be symptom-free.
What are the side effects of agomelatine?
It usually takes several days to weeks for the mood-lifting (antidepressant) effect of agomelatine to occur. During this time, the risk of suicidal thoughts may increase. Doctors therefore pay particular attention at the start of therapy to whether the patient’s depression worsens.
These side effects occur particularly at the beginning of agomelatine therapy. In addition, patients react differently to the active substance. Avoid operating machinery or driving until no more impairing symptoms (such as dizziness) occur.
The active substance may damage the liver. In rare cases, the organ becomes inflamed (hepatitis). Before patients receive agomelatine, doctors therefore check their liver values. They do the same at regular intervals during treatment and before each dose increase. Altered liver values can indicate liver function disorders.
Alcohol also puts a strain on the liver. Patients should therefore avoid alcohol while taking agomelatine.
Sometimes patients sweat more while taking agomelatine (hyperhidrosis). In addition, the skin may itch or develop a rash.
For additional information on possible unwanted side effects, see the package insert for your agomelatine medication. Contact your doctor or pharmacist if you notice or suspect any other side effects.
Doctors prescribe agomelatine to adult patients with severe depression lasting at least two weeks. Doctors also refer to this as major depression.
In Switzerland, patients for whom agomelatine has helped sufficiently against the depression are also given the active ingredient for maintenance therapy. This means that patients take agomelatine for a further six to twelve months to prevent a relapse into depression.
Off-label physicians use agomelatine to treat sleep disorders in adults.
How agomelatine is used
Patients usually take 25 milligrams of agomelatine per day. They swallow the tablets in the evening shortly before going to bed with some liquid, for example half a glass of water. If the symptoms do not improve after two weeks, the doctor increases the daily dose to 50 milligrams of agomelatine.
Typically, patients take agomelatine for at least six months. If the doctor recommends stopping the therapy, the drug can be discontinued. Agomelatine dosage does not need to be slowly reduced.
When should agomelatine not be used?
Dementia patients as well as patients who are hypersensitive to the active substance or any other component of the drug should not take agomelatine medications.
The antibiotic ciprofloxacin as well as the antidepressant fluvoxamine inhibit the enzyme that breaks down agomelatine. Patients may then not use agomelatine. Read more about this below in the section Interactions!
In certain cases, physicians prescribe the active ingredient only in exceptional cases, such as:
- Diabetes mellitus (diabetes)
- Obesity
- Non-alcoholic fatty liver
- Alcohol abuse or frequent alcohol consumption
- Bipolar disorders
These drug interactions may occur with agomelatine
The antidepressant fluvoxamine and the antibiotic ciprofloxacin are examples of strong CYP inhibitors. Estrogens, such as those contained in oral contraceptives (contraceptive pill), may also inhibit the degradation of agomelatine.
Cigarette smoke can also activate CYP enzymes and thus reduce the efficacy of agomelatine. In particular, heavy smokers (more than 15 cigarettes per day) increase the risk of accelerated degradation of agomelatine.
Agomelatine in children and adolescents
Agomelatine should not be used to treat children and adolescents. There are too few data on safe use in this patient group.
Agomelatine during pregnancy and lactation
Doctors usually prescribe better-studied antidepressants, such as sertraline, to pregnant and breastfeeding women.
How to obtain medicines containing agomelatine
Medicines containing agomelatine require a prescription in Germany, Austria, and Switzerland and are therefore only available from pharmacies with a prescription.
Other important notes on agomelatine
Experiences of taking an agomelatine overdose are rare. Affected individuals often suffer from pain in the upper abdomen, dizziness, fatigue, or confusion.
An antidote to agomelatine is not available. Doctors therefore treat an overdose purely symptomatically. This means they treat the patient’s individual symptoms as needed, for example with drugs that stabilize the circulation.
