In recent decades, trusted first aid resources have recommended stings from man o’ war (Physalia species) be treated differently from other jellies. But when researchers at the University of Hawai’i – Mānoa (UHM) dug into the scientific literature, they found scant evidence to support such individualized first aid. Adding to a recent push for evidence-based sting treatments, members of the Pacific Cnidaria Research Laboratory (PCRL) at UHM teamed up with colleagues in Ireland to investigate which commonly recommended first aid actions (such as rinsing with seawater) are the most effective for Physalia stings. Their results, published this week in the journal Toxins, defy the recent abandonment of historic advice, and suggest that man o’ war stings are no different than other jellyfish stings; the best first aid is to rinse with vinegar to remove any residual stingers or bits of tentacle left on the skin and then immerse in 45°C (113°F) hot water or apply a hot pack for 45 minutes.