Clinical recommendation	Purpose	Evidence rating	References	Comments
Hot water immersion should be used for first aid and treatment of cnidarian (jellyfish) stings.	Analgesia	B	23, 24	Randomized controlled study using 113°F (45°C) water immersion for first aid and treatment of stings from Portuguese man-of-war (Physalia physalis)
Antivenom should be administered to patients with systemic symptoms from black widow spider bites.	Relief of symptoms, analgesia	B	25, 26	Review of case series and additional patient-oriented evidence
Pressure and immobilization should be used as first aid for elapid snakebites.	Delay of systemic absorption of venom from bite site	C	27, 28	Anecdotal clinical observations, some case histories and animal models (with limited number of subjects); technique is still controversial
Skin sensitivity testing should not be performed before administration of antivenom.	Testing has no proven value and carries potential risk	C	28, 41, 42	Opinion from worldwide consensus and a retrospective review of 254 cases
Antihistamines should not be given before administration of antivenom.	Antihistamines do not prevent acute adverse reactions to antivenom	C	9	Synthesis of data from two trials (one randomized, one quasirandomized) involving a total of 206 patients
Dapsone, steroids, antihistamines, and hyperbaric oxygen therapy should not be used to treat envenomation from brown recluse spiders (Loxosceles reclusa).	Ineffective treatments for recluse spider envenomation	C	10–12	Prospective and controlled trials of treatment modalities in rabbits