Because it will lower the concentration of electrolytes in the body and aggravate the symptoms.
The human body after severe heat stroke, because in a large amount of sweating, sweat will take away a lot of salt, resulting in an imbalance of electrolytes within the body, if you drink a lot of water at this time, you will further reduce the effective concentration of electrolytes, and aggravate the condition. This is the main reason why heatstroke patients may experience confusion, muscle spasms, as well as twitching of the hands and feet. You can give a person suffering from heat stroke some light saline water to replenish the electrolytes lost from the body.
First aid treatment for pyrexia
Identification
Pyrexia can manifest itself in a variety of ways, and may include: dizziness, throbbing headache, nausea, extremely high body temperature (oral temperature greater than 39.5 degrees Celsius), red, hot, and dry skin without sweating, a fear of being cold, a rapid, heavy pulse, confusion, slurred speech, and unconsciousness.
Treatment
If any of these signs are seen, it is likely that the situation is sufficiently severe to threaten the patient's life at this point. While attempting to cool the patient down, others around should help call emergency services.
1) Move the patient to a cool place.
2)Cool the patient quickly, regardless of the method used. For example: soak the patient in cool water in the bathtub; place the patient under a cool shower; spray the patient with cool water from watering flowers; wipe the patient's body with cool water; apply cold compresses to the head, armpits and roots of the thighs with a cool, wet towel or an ice pack; or, when the weather is dry, wrap the patient in a cool, water-soaked sheet or clothing and blow hard with a fan.
3)Monitor the patient's temperature and persist in trying to help the patient cool down until the temperature drops to 38 degrees Celsius.
4)If first responders do not arrive in time, continue to call 120 for additional guidance and assistance.
5)Do not give the patient water.
6)Get professional medical help as soon as possible.