In the Mediterranean Sea, unfortunately in summer it is not uncommon for the coveted sea bath to be ruined by the very painful contact with the tentacles of a jellyfish.
In reality there are several species of jellyfish, some even whose contact is capable of causing death, but generally in our seas the result is a burning lesion of the skin which has been compared, improperly, to a burn. Naturally, the effects can vary in relation to the location, the extent of the lesion and the intensity of contact with the tentacles of the jellyfish.
Leaving aside difficult technicalities and names, we can simply say that jellyfish, along the tentacles and in the lower part, have microscopic organelles capable of depositing a substance highly irritating to the skin on the skin.
Immediately after contact, the “poison” pours onto the skin, but portions of tentacles and vesicles still intact filled with the toxic substance are also frequently deposited.
Therefore, after contact there is an immediate reaction with burning, pain and redness of the skin, effects which last a long time also due to the persistence of the toxic substance on the skin, perhaps due to the delayed rupture of the vesicles remaining on site.
After contact with a jellyfish the burning is so strong that it is essential to proceed with a therapeutic treatment, which may partly be a medical competence, but which can be made more effective or even unnecessary if some simple procedures:
- as much as possible of both venom left on the skin and any vesicles or tentacle fragments must be eliminated; this can be done simply by washing the affected part thoroughly, but FRESH, hot or cold WATER MUST NEVER BE USED; in fact, fresh water causes the vesicles to break with a mechanism which in chemistry is called “osmotic”; basically the water is attracted into the vesicles which swell and break, pouring even more poison onto the skin and perpetuating and aggravating the symptoms; it is therefore necessary to wash the part with sea water or, possibly failing that, with salt water or physiological solution; washing with a mixture of sea water and sand is also effective, a rather simple operation to carry out along the beach; more complex methods are also described in the literature, such as “shaving” of the part, but I would avoid so as not to further irritate the already suffering skin;
- it is necessary to inactivate the jellyfish poison remaining on the skin; for this reason there are specific products sold in pharmacies which serve to inactivate the poisonous protein, basically based on very diluted ammonia; but if these remedies were not available quickly there is another system that is only apparently “homemade”; in fact, the poison of the jellyfish of our seas is a protein that is denatured, that is, it is transformed into its form and therefore rendered harmless, if immersed in a solution of 5 x 1000 acetic acid. In reality, tracing a 5×1000 acetic acid solution is really difficult, but common table wine vinegar has a concentration of acetic acid very close to this; therefore a vinegar compress on the affected area is able to cause rapid relief from pain and burning (tested in the Medical Guard a few years ago).
However, these actions are only effective if carried out shortly after contact; the next day, for example, are useless actions.
Contact dermatitis with jellyfish the next day (untreated)
In relation to the extent and general situation of the unfortunate person, further local and/or general measures with cortisone or antihistamines may be necessary to soothe the burning and the effects caused by the poison which in any case has had time to act; but this becomes an intervention of a strictly medical nature and I advise against “do-it-yourself”.
But not only jellyfish, even stepping on a Thracina fish “walking” near the shoreline can be a very painful experience. Also to quickly mitigate the strong local pain caused by the sting of the weever, usually on the sole of the foot, there is a “homemade” and simple system, awaiting possible medical intervention to extract, if necessary, the remaining tip of the fish spine fixed in the skin and for this reason I recommend reading this page: Tracina Sting
Dr. Salvatore Nicolosi
Specialist in General Medicine
(translated from the original language, Italian, with an AI program)