Sympathomimetic Toxidrome

Even if the patient is able to provide a history of which agent was taken, street sympathomimetics are often labeled incorrectly (e.g., a tablet marketed as “MDMA” might actually contain various cathinones).- Josh Farkas

HWN Suggests

Toxidromes; what’s your poison?

The sympathomimetic toxidrome mimics the sympathetic nervous system effects (fight or flight). Alcohol and drug withdrawal present the same way as sympathomimetics, which is why they are grouped together.

The effects of drugs that mimic the sympathetic nervous system are predictable... one can appreciate how the sympathomimetic toxidrome could be mistaken for an anticholinergic toxidrome or vice versa. The distinguishing features are the diaphoresis and pale skin in sympathomimetics, versus flushed, dry skin in the anticholinergic toxidrome.

If we were able to assess bowel sounds, they would be present in the sympathomimetic, versus diminished or absent in the anticholinergic…

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Featured

Sympathomimetic toxicity

Not only intoxication, but also withdrawal from sympathetic suppressants can give rise to a sympathomimetic toxidrome picture.

Previously Featured

Bath Salts: The Ivory Wave of Trouble

Based on studies of similar compounds, mephedrone and MDPV may possess intrinsic stimulant properties owing to their effects on plasma membrane dopamine, norepinephrine, and serotonin transporters, resulting in both reuptake inhibition and direct agonist activity.

Cocaine and Other Sympathomimetics

To remember all of these symptoms, just think about a massive sympathetic nervous system activation. Alpha- and beta-adrenergic receptors are activated, resulting in a patient presenting with a classic sympathomimetic toxidrome. NOTE: More severely toxic patients may be agitated, combative, and hyperthermic. Additionally, patients may present with focal acute pain syndromes, circulatory abnormalities, delirium, or seizures. Clonus does not occur with acute cocaine toxicity. NOTE: Typically, end organ damage is rare. However, if there is end-organ damage, it is manifested as an acute hypertensive emergency

MDMA Toxidrome

Classically, MDMA ingestion manifests itself as a sympathomimetic toxidrome, as noted by restlessness, agitation, diaphoresis, mydriasis, tachycardia, bruxism, and hypertension. While these may be mild in intensity for modest ingestion, larger ingestions can lead to confusion, aggressive behavior, muscle tension, psychosis, hyperthermia, tachyarrhythmias, and seizures.

Sympathomimetic vs. Anticholinergic Toxidromes

The clinical picture of sympathomimetic and anticholinergic can appear similar. Both may have agitation, confusion, delirium, seizures, tachycardia, hypertension, fever, and mydriasis. Distinguishing characteristics for anticholinergic syndrome are dry skin, absent bowel sounds, and urinary retention. Remember the colloquial description for anticholinergic toxicity; “Blind as a bat, mad as a hatter, red as a beet, hot as Hades (or hot as a hare), dry as a bone, the bowel and bladder lose their tone, and the heart runs alone.” Both sympathomimetic and anticholinergic syndrome respond well to benzodiazepines. Physostigmine can be used to treat delirium associated with anticholinergic syndrome after checking the EKG for signs of Na channel blockade.

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Whole bowel irrigation: consider in body packers.

StatPearls

Stimulants have been abused for hundreds, if not thousands, of years because they can increase a person's ability to maintain focus and work for longer hours with less fatigue. The current use is very limited in the medical field, most notably in attention deficit hyperactivity disorder, and its recreational use is mostly seen in those seeking to get high or prolong their awake period.