It may be difficult to distinguish between clinical features of depression, adverse effects of selective serotonin reuptake inhibitor antidepressants, discontinuation effects and the potentially life-threatening serotonin syndrome. The table below outlines some common features and others that may help identify the problem. A serotonin syndrome can be a medical emergency, while patients with other problems which do not rapidly resolve should be referred for a psychiatric opinion.
|Distinguishing between clinical features of a medication discontinuation syndrome, adverse events, depression symptoms (or exacerbation) and a serotonin syndrome|
|Discontinuation||Adverse events||Depression||Serotonin syndrome|
|Clinical features||Dizziness, nausea, anxiety, headache (most commonly reported symptoms)||Asthenia, diarrhoea, nausea, anxiety, dizziness, insomnia, nervousness, somnolence, tremor (most common symptoms)||Depression and lack of interest predominate, but can have prominent anxiety and sleep disorder||Abdominal cramps, diarrhoea, tremulousness, myoclonus, coma, tachycardia, hypo- or hypertension, confusion, disorientation, diaphoresis, hyperpyrexia, etc.|
|| || |
|Response to increased SSRI dose||Usually relieved||Usually worsens||No acute change, except possible adverse event||Worsens - could be dangerous|
|Response to decreased SSRI dose||Usually worsens||Usually relieved||No acute change, or subsequent worsening with relapse, or discontinuation syndrome||Usually relieved if SSRI ceased, and ceasing interacting medicines if possible|
|Symptoms persist despite intervention||Seek a psychiatric second opinion||Seek a psychiatric second opinion||Seek a psychiatric second opinion||Emergency, seek immediate second opinion, possibly hospitalise|
Note: There may be overlap between these conditions and the differentiation may be clinically difficult.