Toxidromes

Toxidrome is a term which is used to describe a constellation of signs and symptoms, which when taken collectively, may characterize the poison in question. This is particularly important if patient has altered sensorium, and there is no reliable informant for a medical history. It may be important to review physical features and the differential diagnosis of the... 

Chronic ingestion of greater than therapeutic amounts of atropine may produce symptoms of the anticholinergic toxidrome. 

Opioid toxidrome effects include miosis, respiratory depression, and CNS depression. More serious... 

Acute toxicity induced by pentazocine is primarily associated with central nervous system (CNS) effects that include dizziness, anxiety, hallucinations, mood alterations, and seizures. Respiratory depression, increased PaCOi levels, pulmonary edema, and apnea may occur. Tachycardia, increased systolic and diastolic blood pressure, pinpoint pupils, nausea, vomiting, and abdominal pain have also been reported. In a recently published case series, 40% of acute pentazocine overdose patients did not have the classic opioid toxidrome of CNS and respiratory depression with miosis. 

Symptoms may begin within 1-4 h after ingestion. Jimson weed causes the anticholinergic toxidrome characterized by tachycardia, mydriasis, dry flushed skin, decreased bowel sounds, urinary retention, sedation, and hallucinations. Symptom resolution may vary from 1 day to 2 weeks. 

The toxidrome of acute and chronic toxicities is no defined. Subjective symptoms include nausea, vomiting, flatulence, fatigue, muscle weakness, headaches, and blurred vision. Controversy exists over whether excessive vitamin E may cause liver and renal damage. The plasma concentration levels for vitamin E vary among individuals. 

Toxic syndromes ( toxidromes ) are clinical syndromes that are essential for the successful recognition of poisoning patterns. A toxidrome is the constellation of clinical signs and symptoms that suggests a specific class of poisoning. The most important toxidromes are (1) anticholinergic, (2) cholinergic, (3) opioid and opioid withdrawal, (4) sedative-hypnotic and sedative-hypnotic withdrawal, and (5) sympathomimetic. Symptoms for these toxidromes are listed in Table 34-2. 

Cyclobenzaprine, a tricyclic amine structurally very similar to amitriptyline (see Figure 34-10), is used as a centrally acting skeletal muscle relaxant. Like amitriptyline, cyclobenzaprine causes sedation, produces central and peripheral muscarinic blockade, and potentiates adrenergic actions. In overdose, cyclobenzaprine may cause a typical anticholinergic toxidrome and cardiac arrhythmias, hypotension, and coma. However, cyclobenzaprine overdose is not as frequent nor as lethal as amitriptyline overdose. 

As for codeine, oxycodone is frequently formulated in combination with aspirin (Percodan) or acetaminophen (Percocet and Tylox). Therefore the detection of either salicylate or acetaminophen along with codeine or oxycodone in the urine of patients who display an opiate toxidrome should lead to the measurement of salicylate or acetaminophen in serum to assess their toxicity (see Salicylate and Acetaminophen sections). Alternatively, empiric quantitive serum acetaminophen and salicylate determinations are... 

Nice A, Leikin JB, Maturen A, Madsen-Konczyk LJ, Zell M, Hryhorczuk DO. Toxidrome recognition to improve efficiency of emergency urine drug screens. Ann Emerg Med 1988 17 676-80. 

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