Dizziness Dr Trisha Macnair Being dizzy may be a feature of a huge and varied range of medical problems.

In this article

What are the symptoms?

What causes it?

Can it be serious?

Feeling dizzy is a universal human experience, but we all tend to mean slightly different things when describing it.

Some people may be describing a sense of light-headedness, while others simply mean they feel wobbly on their feet. They may have a feeling that the room is whirling around, although this is more properly called vertigo, especially if accompanied by nausea and vomiting.

Viral infections are among the most common causes of dizziness, especially those that affect the air passages in the head or the ear and result in a disruption of the inner ear. In labyrinthitis, for example, the fluid-filled canals in the inner ear that play a vital part in balance become inflamed.

Other problems with the inner ear that can cause dizziness include Meniere's disease, which results from degenerative changes or ageing, and benign paroxysmal positional vertigo (BPPV) where any sudden movement of the head (usually head turning) can bring on an acute attack without warning.

If your normal blood pressure tends to be low, you're more likely to experience dizzy spells.

Many attacks of dizziness are caused by momentary, harmless drops in blood pressure, leading to a transient reduction in the blood supply to the brain. This typically happens when getting up suddenly from a sitting or lying position and is known as postural or orthostatic hypotension.

This may be aggravated by certain medications, especially those used to control high blood pressure.

In older people with arthritis of the spine in the neck, tilting the head back or twisting it from side to side can temporarily cut off the blood supply to part of the brain and induce dizziness. This is called vertebrobasilar insufficiency.

More serious disruption of the blood supply to the brain, such as a transient ischaemic attack or stroke, may cause dizziness.

Anxiety and panic attacks, especially when accompanied by hyperventilation, can lead to dizzy spells. These may be accompanied by tingling fingers and headaches.

Low blood sugar (hypoglycaemia) is another possible cause, and is easily remedied by eating some sugary food.

Other rarer causes of dizziness include:

• Drug treatments
• Migraine
• Abnormal heart rhythms
• Stress
• Tiredness
• Anaemia
• Acute intoxication
• Carbon monoxide poisoning

In most cases, dizziness is a minor annoyance, but there are a few warning signs that there may be a more serious underlying problem.

The most important of these is loss of consciousness. If someone complains of feeling dizzy on several occasions and then passes out, they should be seen by a doctor. It may be a simple faint that can be easily explained. But if this happens more than once, they should visit their doctor to get it checked out.

Other possible danger signs include:

• New and intense headaches
• Strange sensations or memory changes
• Odd behaviour
• Family history of diabetes or epilepsy

This article was last medically reviewed by Dr Rob Hicks in January 2008