What is serotonin syndrome - a complication of the treatment of depression with drugs with a serotonin mechanism of action, especially from the group of so-called SSRIs. SSRIs(selective serotonin reuptake inhibitors ), but also in combination treatment of SSRIs with TLGCFs (tricyclic antidepressants), SNRIs (serotonin norepinephrinereuptake inhib itors), MAOs (monoamine oxidase inhibitors - an enzyme that inactivates serotonin).
Table of contents:
- Causes of serotonin syndrome
- Symptoms of serotonin syndrome
- Differentiation
- Management of serotonin syndrome
- Drugs that cause serotonin syndrome
Causes of serotonin syndrome
Occurs as a result of a rapid and significant increase in serotonin levels at the nerve synapse, which occurs through blockade of serotonin reuptake by serotonin reuptake inhibitors (SSRIs) and serotonin-inactivating enzyme blockade(MAO drugs), or through an excess of the serotonin precursor L-tryptophan (Kalma, Optimax)
Prevalence - no data available.
When can serotonin syndrome occur?
- following the use or dose increase of a drug with serotonin effects,
- during combination treatment of so-called poly-pragmasy, e.g. several antidepressants with similar serotonin-enhancing effects at the synapse. SSRIs used in combination with MAO inhibitors, L-tryptophan or lithium.
The very slow elimination of SSRI drugs from the body should be mentioned here:
- The half-life (t2) for fluoxetine is 2-7 days and its metabolite norfluoxetine 7-9 days, sertraline 1 day and its metabolite N-desmethylsertraline 3-5 days. The potential duration of action of fluoxetine is therefore approximately 5 weeks.
- The T2 for cloimipramine is 20-25 hours and fluvoxamine about 15 hours.
Symptoms of serotonin syndrome
Similar to those occurring in the course of SSRIs(malignant neuroleptic syndrome), it can therefore be difficult to recognise during treatment with SSRIs and neuroleptics. The characteristic feature that distinguishes the two syndromes is the increase in CPK(creatinine kinase) in AS, remaining unchanged in serotonin syndrome.
- disturbances of consciousness- haziness,
- symptoms of hypomania - elevated mood, cheerfulness, etc,
- tremors and muscle spasms,
- increased tendon and peroneal reflexes,
- impaired coordination of movements,
- chills, sweats and hyperthermia,
- diarrhoea,
- convulsions.
Differentiation
Differentiate with poisoning, abstinence syndromes, metabolic disorders and PMS (see above)
Management of serotonin syndrome
- immediate discontinuation of drugs that may cause the syndrome (see above) - clinical improvement usually within 24 hours,
- monitoring of basic vital functions - circulation, respiration - oxygen therapy, use of ventilator in respiratory failure,
- administration of antipyretics and muscle relaxants - BDZ e.g. diazepam (Realanium, Relsed) up to 100mg / 24h, clonazepam (Clonazepan, Rivotril) up to 1.5mg/24h, lorazepam (lorafen) up to 6mg/24h,
- rehydration (drip infusions) and lowering of body temperature - cold compresses on the body, forced air circulation,
- reduction of blood pressure by administration of nifedipine (Cordafen, Cordipin, Cordipin retard) up to 80 mg / 24 h.
Serotonin syndrome, photo: pantherstock
Drugs that cause serotonin syndrome
Drugs in the SSRI group:
- Fluoxetine (Prozac, Fluoxetine, Bioxetin, Seronil, Deprexetin).
- Paroxetine (Seroxat, Rexetin, Aropax, Paxil).
- Sertraline (Zoloft, Asentra, Stimuloton, Sertagen).
- Fluvoxamine (Fevarin, Floxytral, Faverin).
- Ciltalopram (Cipramil, Cital).
- Escitalopram (Lexapro, Mozarin, Depralin, Aciprex).
Other drugs that in combination with SSRIs may cause serotonin syndrome:
- TLGCF group drugs: Clomipramine (Hydiphen, Anafranil).
- MAOIs: Moxlobemide (Mocloxil, Moklar).
- Drugs in theSNRI group: Venlafaxine (Efectin, Faxigen, Faxolet).
