Doctorweblog. About Health & Medicine

Migraine remedies often contain a drug to reduce nausea and vomiting (antiemetics), as well as a pain-killer. One problem in migraine, is that absorption from the stomach is much reduced once an attack starts, so that pain-killers taken by mouth have little effect. Anti-emetics can improve the absorption of the painkiller, so they are useful for migraines, even if nausea is not a symptom. The main drugs used are buclizine, cyclizine and metoclopramide. These are safe drugs with few side effects.

Because of the problem of non-absorption, it is very important to take migraine treatments as soon as an attack begins – or in advance, for those patients who have advance warning of their attacks, in the form of visual

disturbances, mood changes etc

Composition of migraine

preparations containing painkillers and other drugs

Midrid – paracetamol, plus a sedative, and a sympathomimetic

Migraleve – paracetamol, codeine and buclizine (anti-emetic) in the pink tablets; paracetamol and codeine in the yellow tablets.

Migravess – aspirin and metoclopramide

Paramax – paracetamol and metoclopramide (anti-emetic)

*438\180\8*

Fish: the family concept is irrelevant when it comes to fish, because all the fish in the main group eaten (the bony fish) share a special type of protein known as a parvalbumin. The paralbumins are known to provoke allergic reactions, and they probably account for the fact that many people are sensitive to all the types of fish they have tried. It is uncertain whether paralbumins are found in the other main group of fish, the sharks, rays, skates and dogfish (cartilaginous fish). The two groups are only very distantly related, and it is possible that people sensitive to bony fish could tolerate cartilaginous fish.

Crustaceans, Phylum Crustacea:

crab, lobster, crayfish, shrimp, prawn. A very large group, including many different families. Many patients react to all forms of Crustacea, so the family concept does not seem relevant here. There may be.some common allergen in all of them, as in fish. Also see the section on unexpected reactions, below.

Molluscs, Phylum Mollusca:

mussels, cockles, winkles, oysters, clams, scallops, squid, cuttlefish, octopus, snails (escargots). Again, this is a very broad group, but the family concept does not seem to be relevant here, because people who are sensitive to one type are usually sensitive to them all.

*391\180\8*

Others who may be concerned about their nutritional status, but cannot afford individual testing and see if they show any signs of deficiency. These are not foolproof signs, however – the same symptoms can be produced by other forms of illness, and there are several deficiencies that do not appear in the table because they produce no clear-cut signs. But if you do show some of these signs, then there is a chance that you are lacking certain nutrients, especially if your diet has not been good. The simplest and cheapest answer is to take a general supplement. This may be slightly more expensive than run-of-the-mill vitamin tablets but it is far more likely to do you good – and not to do you any harm. It is also free of artificial colours, unlike most commercial preparations which come in lurid shades of red or orange as an indication of their health-giving properties! Avoiding colourings is important if you are embarking on an elimination diet.

One sign that you may notice is white spots on the fingernails. These can be an indication of zinc deficiency, and if you show no other deficiency signs, and generally eat a good diet, then taking a zinc supplement may be all you need to do. Zinc is relatively safe and non-toxic, so a sensible supplement is unlikely to do any harm.

*344\180\8*

There is evidence that people with food intolerance have more leaky gut walls than healthy individuals – so they let more undigested food molecules through. This has major health implications which will be considered later, but how does the gut become more leaky in the first place?

Inflammation, produced by immune attack, can make the gut wall more leaky. One source of inflammation is disease – any gut infection that produces diarrhoea may inflame the gut wall. In babies, such infections are often the start of food intolerance.

Alternatively, foods themselves might provoke inflammation of the gut wall, if there is a localized allergic response to them. This is not something that most allergists would agree with – they see IgE/mast cell reactions to foods (see p29) as being all-or-nothing affairs which produce immediate and unmistakable symptoms. The idea that there might be a small-scale, localized IgE reaction, whose main effect is to make the gut more permeable, is not widely accepted. The main evidence in its favour is the effect of a drug, sodium cromoglycate, on some patients with food intolerance.

The effects of this drug have mainly been studied in migraine patients. If such patients undertake an elimination diet, a large proportion of them get better and can then identify one or more foods which provoke their symptoms. Each time a culprit food is eaten it will provoke a migraine -but not if sodium cromoglycate is given in advance. Sodium cromoglycate is

known to stabilize mast cells and prevent them from releasing their inflammatory mediators. And the drug is not absorbed from the gut in any appreciable quantity. So the logical conclusion is that it prevents reactions to culprit foods by blocking mast-cell reactions in the gut wall.

There is a third way in which the gut wall might be made more leaky. We all produce a special type of IgA antibody called secretory IgA or SIgA. The production of SIgA is stimulated by the Peyer’s patches, and it pours out into the gut, where it binds to its target antigen. By binding to antigens, and locking them into immune complexes, SIgA effectively makes them much bigger. The bigger they are the more difficult it is for them to pass through the gut wall. So SIgA reduces the number of food molecules that cross the gut wall – and the number of microbes, because SIgA is made to these as well. Like IgA in the blood, SIgA does not cause any inflammation.

There is some evidence that people with food intolerance have less SIgA than healthy people. However, there are patients who have severe deficiencies of SIgA, and, although they are ill in other ways, they show no more signs of food sensitivity than the population at large. This suggests that SIgA deficiency alone is not enough to cause food intolerance.

*296\180\8*

As children get older, their early symptoms often disappear or at least diminish, although they may often be replaced by another type of allergic disease. Whether the majority of children do actually ‘grow out of it’ as doctors so often state is a debatable point. It may be that the outward signs of the allergy subside but that the underlying condition persists, especially in the case of an allergen to which the patient is exposed on a regular basis, such as cow’s milk or eggs. Some doctors who specialize in treating food allergy believe that the allergic reaction is simply suppressed by the body temporarily, but that it will recur in adult life, possibly in a different form. There is no solid evidence to support this idea but it is not entirely implausible. Many people who have asthma or eczema as children later ‘grow out of it’, but then succumb to other health problems in their twenties, thirties or forties.

If this theory is correct, it might be better to investigate their allergic problems more closely in childhood, and, in the case of food allergens, to eliminate the incriminated foods from their diet, rather than simply waiting for them to ‘grow out of it’. Experience shows that cutting out allergenic foods for a period of time – for a few months, a year, or sometimes longer – can often eliminate the sensitivity in the long term, as well as providing more immediate relief from the child’s symptoms. But there are a variety of other factors to consider – some of which will be discussed in more detail later.

*45\18\8*