Trimipramine is a drug that is used to treat mainly depressive states, although it is also prescribed in the case of sleep and anxiety disorders, as well as some psychosomatic disorders. Because of its high risk of adverse effects, this drug is usually prescribed under strict medical supervision.

Next we will see what trimipramine is, what it is for, what its possible adverse effects are and how it is marketed.

What is trimipramine and what is it used for

Trimipramine is a tricyclic antidepressant that has sedative and anticholinergic properties . The latter act both centrally and peripherally on the nervous system. Its mechanism of action is not fully known, but it is chemically related to another tricyclic-type drug called imipramine.

Tricyclic and tetracyclic antidepressants are two of the first to be used in psychopharmacology. They are drugs that prevent the reuptake of serotonin, and sometimes noradrenaline, in the synaptic space, which produces a high concentration of these neurotransmitters and a reduction in some symptoms of depression .

Trimipramine is used primarily to treat depressive conditions, whether they are mild or severe. But it is also used for the treatment of psychosomatic disorders that have a depressive background, as well as for states of anxiety and sleep disturbance. The improvement associated with this drug usually occurs after the first few weeks, or sometimes a little longer, from the start of treatment.

At the same time, i.e. during the early stages of recovery, the risk of suicide that often accompanies depression may increase . Therefore, it is recommended to accompany the person closely until the first signs of improvement occur.

In fact, until recently, tricyclic and tetracyclic drugs were among the most widely used antidepressants. However, because they have a non-specific mechanism of action, these drugs often affect other substances important to the body (such as acetylcholine, histamine and dopamine). This increases the probability of suffering adverse effects, as well as mortality from overdose, so their prescription has been reduced.

Route of administration and recommended dose

The trade name of trimipramine is Surmontil and is marketed in tablets containing 35 mg of trimipramine maleate , which is equivalent to 25 mg of the active ingredient.

Surmontil is administered orally, and if prescribed to treat minor depressions, psychosomatic conditions, or sleep and anxiety disorders, is usually given as a single dose between 12.5 mg and 50 mg , usually at night. On the other hand, in the case of severe depression, it is generally recommended to take 300 mg to 400 mg a day in 2 to 3 doses. It is valid for 5 years and should be stored at a temperature not exceeding 25°C.

Also, when it becomes necessary to reduce the doses, the general recommendation is to do so progressively and to monitor the risk of deprivation syndrome.

Possible side effects

As with other tricyclic antidepressant drugs, the adverse effects of trimipramine are as follows:

  • Weight loss .

    • .

  • Endocrine problems, such as breast hypertrophy or galactorrhea
  • Allergic skin reactions .
  • Hematological difficulties.
  • Syncope.
  • Dry mouth and urinary retention.
  • Elevation of psychomotor inhibition.
  • Mood swings with appearance of manic episodes.
  • People over 50 are at greater risk of bone fractures.
  • Suicidal ideation and behaviour , especially in people under 25, studies have shown that this occurs once treatment has started or as soon as it ends.
  • Serotonergic syndrome, which can be fatal and can produce neuromuscular excitation, autonomic changes and changes in mental state; and which can occur when this drug is mixed with other serotonergic active ingredients.
  • Disorders of the nervous system, which can be caused by the peripheral effects of trimipramine, by its central effects or by the very nature of depression.
  • Heart disorders .
  • Metabolic and nutritional disorders.

Contraindications and interaction with other substances

Trimipramine is contraindicated in children under 12 and in people who have a history of suicidal ideation and attempt. Also, trimipramine has the risk of producing liver and kidney failure.

Should not be mixed with MAOI-type antidepressant drugs , or administered in periods close to the last time they were taken. Also, mixing trimipramine with SSRI-type antidepressant drugs, such as fluoxetine and fluvoxamine, increases the risk of toxicity.

The sedative effect of this drug is enhanced when mixed with sedatives, morphine derivatives, barbiturates, antihistamines, anti-anxiety drugs, methadone, clonidine and hypnotics. The same is true if this drug is mixed with alcoholic beverages. There is also a risk of generalized seizures if this drug is mixed with anti-seizure medications .

Because of the possibility of its excretion in breast milk, it is not recommended to use this drug during the period of lactation. There is also the possibility of secretion by the placenta, so it is not advisable to use it during pregnancy .

Also, as with other psychoactive medications, this antidepressant can alter some physical and psychological faculties, so it is recommended that you take precautions when driving or operating heavy machinery.

Bibliographic references:

  • Spanish Agency for Medicines and Healthcare Products (2016). Technical File, Surmontil. Recovered August 16, 2018. Available at https://www.aemps.gob.es/cima/pdfs/es/ft/40115/40115_ft.pdf.
  • Vademecum (2016). Trimipramine. Recovered August 16, 2018. Available at https://www.vademecum.es/principios-activos-trimipramina-n06aa06.