Note: The symptoms of heat illness described below (heat cramps, heat exhaustion, and heat stroke) can develop completely independently of each other and seemingly abruptly, i.e., there is no particular sequence of specific stages of illness.
The following symptoms and complaints may indicate sunstroke:
- High red hot head
- Pale, sweaty skin
- Nausea (nausea)/vomiting
- Cephalgia (headache)
- Vertigo (dizziness)
- Meningismus (symptom of painful neck stiffness in irritation and disease of the meninges).
- Drowsiness
- Disturbance of consciousness
Harbingers of heat exhaustion are vigorous redness of the skin, high perspiration (resulting in dehydration) with dry mucous membranes and severe headache.
The following symptoms and complaints may indicate heat exhaustion:
- Short-lasting loss of consciousness (syncope; in this case, heat syncope), often heralded by dizziness and nausea (nausea)/vomiting.
Heat syncope typically occurs after a latency in time.
The following symptoms and complaints may indicate heat cramps:
- Vertigo (dizziness)
- Weakness
- Muscle cramps (most often affects local working muscles; typically calf cramps in running)
Accompanying symptoms as a result of the heat
- Heat rash (so-called miliaria) – occurs mainly in regions with warm and humid climate.
- Heat edema of the legs (swelling of the legs due to heat).
Note: Symptoms such as weakness, headache, and nausea as seen in heat cramps may also occur simultaneously in heat exhaustion.
The following symptoms and complaints may indicate heat exhaustion:
- Weakness
- Nausea (nausea)/vomiting
- Chills
- Diarrhea (diarrhea)
- Visual disturbances
- Cephalgia (headache)
- Ringing in the ears
- Muscle weakness
- Anuria (maximum 100 ml of urine per day).
- Circulatory insufficiency (circulatory weakness)/shock signs.
- Psychoneurotic disorders (aggressiveness, agitation, confusion).
Note: In heat exhaustion, cool skin temperature can be misleading!
Symptoms of salopriven heat exhaustion (salt depletion) can develop over several days (3-5 days).
Cave: heat exhaustion can progress to heat stroke.
The following symptoms and complaints may indicate heat stroke (= life-threatening heat illness):
Leading symptoms
- Severely elevated body temperature (> 41 °C rectally).
- Disturbances of consciousness → unconsciousness (3 points on the Glasgow Coma Scale (GCS): see below “Physical examination“).
- Motor agitation
- Fatigue
- Anxiety
- Vertigo (dizziness)
- Visual disturbances
- Delir
- Coma
- Warm reddened skin, dry (ie no more sweating).
- Shallow breathing with increased frequency
- Progressive ataxia (increasing movement disorder).
- Seizure (generalized seizure).
