Health Centres - Prothiaden (dosulepin)
How does it work?
Prothiaden capsules and tablets contain the active ingredient dosulepin (previously known as dothiepin in the UK), which is a type of medicine called a tricyclic antidepressant (TCA). This type of medicine acts on nerve cells in the brain. (NB. Dosulepin is also available without a brand name, ie as the generic medicine.)
In the brain there are numerous different chemical compounds called neurotransmitters. These act as chemical messengers between the nerve cells. Serotonin and noradrenaline are neurotransmitters and they have various functions that we know of.
When serotonin and noradrenaline are released from nerve cells in the brain they act to lighten mood. When they are reabsorbed into the nerve cells, they no longer have an effect on mood. It is thought that when depression occurs, there may be a decreased amount of serotonin and noradrenaline released from nerve cells in the brain.
Dosulepin works by preventing serotonin and noradrenaline from being reabsorbed back into the nerve cells in the brain. This helps prolong the mood lightening effect of any released noradrenaline and serotonin. In this way, dosulepin helps relieve depression.
Dosulepin can cause side effects such as drowsiness. This means it may be useful in treating depression in people who are also anxious and agitated, or who are suffering from disturbances in sleep.
It may take between two to four weeks for the benefits of this medicine to appear, so it is very important that you keep taking it, even if it doesn't seem to make much difference at first. If you feel your depression has got worse, or if you have any distressing thoughts or feelings in these first few weeks, then you should talk to your doctor.
What is it used for?
- Depressive illness.
Warning!
- Depression is associated with an increased risk of suicidal thoughts, self-harm, and suicide. You should be aware that this medicine may not start to make you feel better for at least two to four weeks. However, it is important that you keep taking it in order for it to work properly and for you to feel better. If you feel your depression has got worse, or if you have any distressing thoughts or feelings, particularly about suicide or harming yourself in these first few weeks, or indeed at any point during treatment or after stopping treatment, then it is very important to talk to your doctor.
- This medicine may cause drowsiness and could reduce your ability to drive or operate machinery safely. Do not drive or operate machinery until you know how this medicine affects you and you are sure it won't affect your performance.
- It is recommended that you avoid drinking alcohol while taking this medicine because it may enhance drowsiness.

