Acute Kidney Injury
| Acute Rhabdomyolysis
Serotonin syndrome occurs most commonly soon after starting such medication or when the treatment dose is increased or an overdose is taken. The combination of a monoamine oxidase inhibitor (MAOI), in particular, MAO-A inhibitors that preferentially inhibit the metabolism of 5-HT, with serotonergic drugs is especially dangerous
- Excess serotonin (5-Hydroxytryptamine) may be due to overdose of SSRI, fluoxetine and sertraline
- Potentially life-threatening drug-induced toxidrome
- Increased serotonergic activity in peripheral (PNS) and central nervous systems (CNS).
Causes: together drugs may be additive
- Antidepressants: MAOIs, TCAs, SSRIs, SNRIs, trazodone and mirtazapine.
- Opiates: Pethidine, fentanyl, buprenorphine, oxycodone, tramadol.
- CNS stimulants: MDMA, phentermine, amphetamines, sibutramine, methamphetamine, cocaine
- Herbs: St John's Wort, ginseng, nutmeg
- Others: Valproate, buspirone, lithium, linezolid, chlorpheniramine, risperidone, olanzapine, ondansetron, granisetron, metoclopramide.
- Inducible or ocular clonus with agitation or diaphoresis
- Tachycardia, shivering, sweating, mydriasis, diarrhoea
- Myoclonic jerks, hyperreflexia, clonus, hyperthermia.
- Increased vigilance and agitation. Metabolic acidosis
- Rhabdomyolysis. DIC, AKI, seizures.
- FBC, U&E, LFTS, CRP, CK, lactate, Glucose, ABG
- 12 lead ECG, CXR and Urine if sepsis considered
- Unclear check CT head and LP/CSF ? HSV ? Encephalitis
Management[Get expert help early]
- ABC, Consider HDU if low GCS, High Temperature, AKI, Seizures
- Mainly supportive. Stopping serotonergic drugs usually brings about a rapid improvement.
- IV Diazepam 5-10 mg for seizures and agitation and can reduce muscle tone.
- Aggressive cooling if temperature over 40 C
- IV fluids 1-2 Litres and as needed. Supportive. Beta blockage for arrhythmias.
- Watch U&E, K, CK and Lactate and ABG for deterioration
- Diazepam 10mg IV. Can be repeated. Large doses may be required.
- Cyproheptadine 12mg PO/NG stat then 8mg every 6 hours.
- Chlorpromazine 25mg IM
- Dantrolene 1-2.5mg/kg. Can be repeated up to a maximum of 10mg/kg.
- Rhabdomyolysis consider 1.26% bicarbonate therapy
- IV Glucose 10% if hypoglycaemia
- Should settle once causative drug stopped.
- Avoid opiates with intrinsic serotonergic activity