Hot, dizzy and nauseated: what to know

Dizziness may feel like light-headedness, unsteadiness, or the room spinning. Feeling overheated can come before or alongside nausea, especially after exertion or time in a hot place. Notice whether symptoms improve when you sit or lie down, cool off, and take fluids.

Heat exhaustion can cause heavy sweating, weakness, dizziness, headache, nausea, and a fast pulse. Food poisoning or gastroenteritis may add vomiting, diarrhoea, cramps, or fever. Acid reflux and gastritis more often cause nausea with upper-abdominal discomfort, burning, or an unpleasant taste. Gallstones can cause nausea with strong pain in the upper right or upper middle abdomen.

Low blood sugar may cause sweating, shakiness, hunger, weakness, dizziness, or confusion, particularly in someone using diabetes medicine or who has not eaten. Hepatitis A can cause nausea and tiredness with dark urine, pale stools, abdominal discomfort, or yellowing of the eyes or skin.

Stop exertion and sit or lie somewhere cool. Loosen tight clothing, cool your skin with a damp cloth, and take small, frequent sips of water or an oral rehydration drink if you can swallow normally. Avoid alcohol and large, heavy meals while nausea is active.

If you have diabetes and can safely check your glucose, follow your personal low-glucose plan. Do not give food or drink to someone who is drowsy, confused, or unable to swallow. Keep a note of recent meals, fluid intake, medicines, heat exposure, vomiting, bowel changes, and pain.

Seek urgent medical help for fainting, new confusion, difficulty speaking, weakness on one side, severe headache, chest pain, trouble breathing, repeated vomiting, blood in vomit or stool, or severe abdominal pain. Emergency assessment is also needed if a person remains very unwell after moving to a cool place and taking fluids.

Contact a clinician promptly if symptoms recur, you cannot keep fluids down, you are passing very little urine, or you develop yellow skin or eyes. Children, older adults, pregnant people, and people with diabetes or chronic illness can become unwell more quickly.

Ask which cause best fits the timing and associated symptoms, whether you need blood or urine tests, and how to adjust medicines that may affect blood sugar or fluid balance. Mention pregnancy, diabetes, recent travel, heat exposure, and every medicine or supplement you use.