Q I am a 51-year-old man. I keep sweating whenever I eat.

I keep perspiring through all my meals except when I am eating bread, cookies or cold food. I sweat more when I take spicy food.

I drink three to four times a week, mostly beer.

I have at least one vegetable meal a day as my family does not cook much meat.

What can I do to stop sweating so much when I am eating?

A It seems like you may be suffering from an uncommon condition called gustatory hyperhidrosis, which is excessive sweating related to eating.

You did not specify the affected body areas, but this condition commonly affects the face, scalp and neck.

For unknown reasons, people with this condition have an abnormal and exaggerated nervous system response whenever their taste buds get stimulated, which happens when we eat.

These exaggerated nervous-system responses lead to excessive sweating because our sweat-gland activities are controlled by our nerves.

Occasionally, this condition can be related to nerve damage near the parotid glands (cheek salivary glands) from surgery or infection.

Patients with diabetes can also develop this condition.

The simplest treatment to control the excessive sweating is to apply an anti-perspirant twice a day on the affected skin areas when they are completely dry.

The active ingredient - aluminium chloride hexahydrate - mixes with the perspiration to form a salt which blocks the flow of sweat.

After repeated use, you may be able to achieve similar control with less frequent applications.

Another treatment to consider is to take an oral medication. You will need a doctor's prescription for this. It works by blocking the nerve transmission which triggers sweat production and release in the sweat glands.

Do note that this medicine will reduce sweating over the entire body, even in places where sweating is not a problem. Thus, it can put you at risk of heat exhaustion if you take part in strenuous activities.

Some people may experience palpitations, dry mouth, blurred vision, urine retention and constipation.

Finally, in small localised areas, botulinum toxin (Botox) injections can be given to reduce excessive sweating. It also works by blocking nerve transmission signals to the sweat glands.

This effect usually lasts around six months and usually needs to be repeated.

For more information, go to the International Hyperhidrosis Society website (www.sweathelp.org).

Dr Chris Tan

Associate consultant in the division of dermatology at the National University Hospital