Dizziness when it is hot is considered to be due to heat that causes the peripheral blood vessels to dilate, which is conducive to heat dissipation, and the expansion of the peripheral blood vessels leads to reduced blood circulation to the brain, which can lead to dizziness as a symptom of insufficient blood supply to the brain. First of all, dizziness when it is hot is usually seen in people who usually have low body pressure, but also in the elderly, because the contraction function of blood vessels is reduced, the symptoms of insufficient blood supply to the brain can occur, so the patient will appear dizzy. Secondly, dizziness when it is hot can also be caused by heat stroke, as the patient sweats a lot in hot weather and does not replenish water in time, there can be insufficient blood volume, and if the blood volume is not replenished in time, the patient will have critical conditions such as shock in severe cases. If the patient has underlying diseases such as heart disease, arrhythmia, etc., the heat can trigger the occurrence of arrhythmia, and due to changes in the ejection of blood from the heart, it can also affect the blood supply to the brain, and the patient can also experience dizziness, accompanied by symptoms such as panic and shortness of breath.