Iberiotoxin (IbTX) is an ion channel toxin purified from the Eastern Indian red scorpion Hottentotta tamulus.
Iberiotoxin selectively inhibits the current through large-conductance calcium-activated potassium channels.
In rural India the scorpion and its venom is a commonly known factor of children's death.
The venom initially causes transient cholinergic stimulation (vomiting, profuse sweating, bradycardia, priapism, hypersalivation, and hypotension) which is followed by sustained adrenergic hyperactivity (hypertension, tachycardia, and myocardial failure).
Patients with hypertension on admission are given a single dose of 5 mg sublingual nifedipine and oral prazosin.