To be effective, hot water/heat needs to be applied rapidly after a sting. Methods of application include:
- Immersion of the affected body part in water maintained at 45°C for 20 minutes
- Basin/bath filled with hot water (checked with a thermometer)
- Hot shower (advantage of being able to vary the temperature, but it is often difficult to know the exact temperature)
- Heat packs
As hot water immersion, especially with maintained temperatures, is seldom available at beach side locations, self-heating heat packs may be the most convenient method, although they have not been proven to be effective or safe.
Consider heat packs with the capacity to reach 45°C for seaside first aid kits. ‘Medi’ heat packs are claimed to heat up to 54°C, and to be reusable. They cost between $12 and $45.
Several other heat packs are available but not all may reach 45°C and some may also exceed this.