Alcohol, allergies and side effects by Dr Philip Norrie

There are other harmful effects one can suffer from consuming alcohol other than those suffered from straight abuse or excessive consumption. These harmful effects are those due to allergy and side effects in general, even with exposure to the smallest quantities of alcohol.

The Collins Dictionary defines allergy as a hypersensitivity to a substance that causes the body to react to any contact with that substance. As a doctor, I define allergy as an immune system mediated response by the body to an allergen or allergy causing foreign matter. Allergies usually manifest themselves as migraine, headaches, hay fever, itch, rashes, bowel colic, diarrhoea, asthma, swollen face and watery swollen eyes etc.

An allergic response is a response to protect the body from allergens - harmful foreign matter that we are exposed to, mainly in the form of pollen, dust, hairs, fibres, food and drink. Sometimes an allergic response can be excessive and the resulting body's 'cure' can be worse than the allergic complaint, even life threatening when sufferers develop an anaphylactic response resulting in the laryngeal oedema or swelling of the throat. If it is not treated straight away with adrenaline, corticosteroids or antihistamines one can choke to death.

Many consumers think that the main cause of allergy in wine for example, is due to sulphur dioxide (SO2), which has been used as a preservative since Roman times. Unless you suffer a similar reaction from eating dried fruit for example, where levels of SO2 are much higher, it is rarely the case. Sufferers are far more likely to be allergic to naturally occurring histamines or tannins present in high doses in red wines, but also in white wines, many beers and some spirits. Allergy however is idiosyncratic, hence the old adage one man's food is another mans poison since one could theoretically allergic to any one of the thousands of components in wine.

A side effect is defined as any unwanted non-therapeutic effect caused by a drug.

There are two rare medical conditions caused by alcohol which would be strictly termed as side effects. The first is where people become aggressive and emotional after ' a few drinks'. The biochemical cause is not understood. The second condition is alcohol induces nymphomania, where consumption of a small amount of alcohol in a person with a pinealoma ( a rare benign tumour of the pineal gland) triggers off intense sexual arousal and subsequent sexual behaviour.

Neither allergy or side effects should be confused with a hangover, which is where one develops head-ache, nausea, vomiting, lethargy and a dry mouth etc. due to excessive alcohol consumption. A hangover is due to dehydration, especially of the brain, which shrinks, pulling on pain sensitive filaments connecting it to the skull. Dehydration is due to the osmotic pressure and diuretic effects of alcohol, frequent urination also results in the loss of sodium and potassium ions which are essential in nerve and muscle function. Finally alcohol depletes reserves of glycogen in the liver, breaking it down into glucose.

To prevent hang-over, drink sensibly and alternate soft and alcoholic drinks at parties for example, and make a point of drinking plenty of water before retiring to bed. So called commercially available hangover remedies such as SOBA , a volcanic zeolite, similar in its actions to charcoal, are not to be recommended.

Dr. Phil Norrie is a General Practioner, vineyard owner, author of Wine and Health- a new look at an old medicine and a member of the AIM Editorial Board.