Clinical course
Initial bite feels like a pinprick. Within 30–60 minutes, severe muscle cramping spreads from the bite site to the abdomen, chest, and back. Hypertension, sweating, and tachycardia are common. Symptoms peak at 6–12 hours and may persist 1–3 days.
Treatment
Opioid analgesia and benzodiazepines for muscle cramping are first-line. Antivenom (Latrodectus mactans equine immune F(ab')2) is reserved for severe envenomation, pregnancy, or hemodynamic instability due to historical hypersensitivity reactions.
Mortality in the modern era is essentially zero in healthy adults; pediatric and elderly cases warrant closer monitoring.
References
- [1]Latrodectism - Black Widow Spider Envenomation - UpToDate. Accessed June 2026.
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