Studies

Brazil
Coelho and Gonçalves 1993: 68 Phoneutria sp. bites. Identification: spiders brought in and identified. Average time between the bite and arriving at the hospital 1.5 h.

Signs & symptoms

Autopharmacological effects

Experimental and clinical observations suggest that the major systemic effects of envenoming are caused by endogenous catecholamines and acetylcholine, which are released in response to Phoneutria sp. venom. As these are transmitters of the sympathetic, parasympathetic and somatic nervous systems, the resulting clinical symptoms of envenoming are dealt with in the section "Neurological effects".

Local effects

Local pain 57/68, local oedema 36/68, local hyperaemia 27/68, local paraesthesia 13/68, local sweating 10/68; referred regional pain 8/68 (Coelho and Gonçalves 1993).

Neurological effects (autonomic and somatic nervous systems)

Phoneutria venom causes the release of neurotransmitters, primarily acetylcholine and noradrenaline. However, the neurological effects of the venom do not seem to be very pronounced in cases of human envenoming (Lucas 1988).

Vomiting 7/68, sweating 4/68, drowsiness or agitation 3/68, arterial hypertension 2/68, tachycardia 2/68 (Coelho and Gonçalves 1993).

Case fatality rate

0/68 (Coelho and Gonçalves 1993).

Treatment (symptomatic)

Local infiltration with lidocaine 34/68. This form of pain treatment was effective in 29 of these 34 patients. Only 5 of the 34 required a second local infiltration with lidocaine (Coelho and Gonçalves 1993).

Treatment (specific)

Local infiltration with lidocaine for the treatment of pain. Bites from these spiders generally do not require any further treatment. The neurological effects of the venom do not seem to be very pronounced (Coelho and Gonçalves 1993, Lukas 1988).