From WebMD on stingray strikes:
[color:"blue"] An easy and important initial treatment that can be started (sometimes at the scene of the injury) is immersion of the injured extremity in hot water (preferably 110-115°F). The water should be as hot as the patient can tolerate but should not cause burns. The water should be exchanged for more hot water as it cools, for an immersion duration of 30-90 minutes.
Very little has been written about the toxin left in wounds after a stingray injury. It is known that the stingray toxin is a protein and is very sensitive to heat. The patient should obtain very rapid symptomatic improvement with heat as the poison denatures and becomes neutralized. Some thought exists that the protein does not truly denature but that some sort of gateway effect occurs on the nerve conduction. Whatever the truth is regarding how heat works, it is a rapid, effective treatment to reduce pain almost instantaneously.
In addition, some practitioners also infiltrate the wound with a local anesthetic, such as lidocaine (lignocaine) or the longer-acting bupivacaine. Occasionally, oral or parenteral narcotics may also be given.
After the toxin has been deactivated by the hot water, attention to local wound care should begin because it is not uncommon for part of the stinging apparatus to break off in the wound.
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