Heatstroke: long term treatment?

Hello my name is Baris. My girlfriend (34 years old) had a heatstroke last summer at a summer place in Turkey. She stayed at the hospital overnight and received an IV fluid treatment. Blood test results showed that her electrolyte levels were below the required levels. We were told by the doctors that dehydration and alcohol consumption (the night before) could have triggered this situation.

After we returned from our holidays she felt nauseous for nearly a month until she got well again.

Two weeks ago we went to Thailand for holidays and she got sick again the first day we spent on the beach. Same symptoms: feeling shaky, dizzy and nauseous. We immediately went to the hospital and had to stay there for four nights (unconscious for the first two nights; she slept continuously) until she was ok to leave the hospital (extensive blood tests were done; results suggested decrease in electrolyte levels, no other problems). She received IV fluid and medicine treatment during this stay.

We returned back from our holidays. The same uncomfortable state continues; she says she is feeling weak and nauseous. Any major temperature change in her surroundings makes her feel weak and nauseous again.

What is the long term treatment of this situation? What do you suggest? Thank you very much.

Best Regards,

Baris U.