Dizzy, light-headed, nauseated and tired

These words can describe different sensations: the room may feel as if it is moving, or you may feel faint, unsteady or generally unwell. The combination and its timing provide useful clues, but symptoms alone cannot identify one cause.

Vomiting, diarrhoea, sweating, fever or not drinking enough can lead to fluid loss and make you feel weak or light-headed. Heat exhaustion can cause tiredness, dizziness, nausea, heavy sweating and headache, especially after time in a hot environment.

Going too long without food, or taking diabetes medicine without enough carbohydrate, can cause low blood sugar. An upset digestive system may also cause nausea and fatigue; possible examples include food poisoning, gastroenteritis, gastritis or acid reflux. Upper-right abdominal pain after eating may occur with gallstones, while yellowing of the skin or eyes needs medical assessment.

Sit or lie down as soon as you feel faint, and rise slowly when the sensation settles. Sip water or an oral rehydration drink if you can keep fluids down. Rest somewhere cool, loosen excess clothing and avoid driving, heights or machinery while dizzy.

If you have diabetes, check your blood glucose if possible and follow the personal low-blood-sugar plan given by your clinician. Choose small, plain meals when nausea eases. Arrange a medical review if symptoms keep returning, interfere with normal activities, or do not improve after rest and fluids.

Seek urgent medical help for fainting, confusion, severe weakness, trouble speaking, new one-sided weakness, chest pain, severe breathlessness, a severe headache, stiff neck, a serious injury or repeated vomiting that prevents drinking.

Prompt assessment is also needed for signs of significant dehydration, blood in vomit or stool, severe or persistent abdominal pain, or yellow skin or eyes. If pregnancy is possible, mention it when seeking advice because nausea, dizziness and tiredness may need a different assessment.

You could ask: What type of dizziness does this sound like? Could dehydration, an infection, low blood sugar, a medicine or another problem explain the symptoms? What warning signs should prompt urgent help? Should I have blood tests or a review of my medicines?

Before the appointment, note when the symptoms began, whether they follow meals or heat, any vomiting or diarrhoea, your fluid intake, medicines, menstrual or pregnancy history, and whether you feel spinning or near-fainting.