Title:Black Widow Spider (Latrodectus mactans) Antivenom in Clinical Practice
Volume: 13
Issue: 10
Author(s): Andrew A. Monte
Affiliation:
Keywords:
Analatro, antivenom, black widow spider, Fab2, Latrodectus mactans, latrodectism, spider treatment, syndrome, tachycardia, hypertension, Opioid analgesics, muscle relaxants, symptomatic, clinical trials, Arachnophobia.
Abstract: Black widow spider (Latrodectus mactans) envenomation has been recognized since antiquity. The syndrome,
latrodectism, is characterized by painful muscle rigidity and autonomic disturbances such as tachycardia, hypertension,
and diaphoresis. Symptoms typically last for 1-3 days. Treatment has ranged from local folk remedies to administration of
specific antivenom. Opioid analgesics combined with muscle relaxants, such as benzodiazepines, are only effective at
symptomatic and temporary control. Antivenom is by far the most efficacious therapy available based on symptom resolution,
need for subsequent therapy, and hospital admission rates. Fear of allergic type reactions from antivenom administration
has limited its use in the United States. A new purified F(ab)2 fragment Latrodectus mactans antivenom, Analatro®,
is currently undergoing clinical trials. The product is expected to have similar efficacy and be associated with fewer adverse
reactions when compared to the currently available partially purified whole IgG Merck product. This shift in the
risk-benefit analysis may ultimately lead to more antivenom administration in significantly envenomated patients.