toring will become clear and the need for a routine service will increase. Why not, then, allow the clinician to get used to molar units now rather than make the inevitable, but painful, change later? The argument that drug dosing is normally on a gravimetric basis has little relevance to the question of what units should be used for drug levels. In fact, there is only one drawback to the discrepancy in units-namely, that a conversion factor must be used when the apparent volume of distribution and clearance of a drug is calculated-not an exercise which the clinician is likely to be involved in very often. While noting your quip about molar weighing machines, I consider that dosing in molar units is the logical outcome in the rationalisation of units. As was pointed out in a more thoughtful British Medical 3’ournal editorial,4 drugs may be given in the form of the base itself or of a salt or other compound of the base, and this may lead to confusion in dosing. How many of your readers know that the yield of theophylline from a 200 mg choline theophyllinate (’Choledyl’) tablet is only 127 mg, and is therefore therapeutically equivalent to a 125
tablet (plain theophylline)? Furthermore, how that a 192 mg ’Heminevrin’ capsule is equivamany lent in potency to a 500 mg heminevrin tablet (the former contains chlormethiazole base while the latter contains the edisylate). Perhaps readers of the small print in data sheets know this, but it did not prevent an editorial error5 in conversion of gravimetric to molar units. If all drug doses were given in moles of the active substance this source of confusion would be eliminated. Perhaps the change will be difficult, but as drugs become more potent there is no longer a place for a system which encourages their imprecise use.
of Clinical Pharmacology, St. Bartholomew’s Hospital, London EC1A 7BE
ETHICAL PROBLEMS OF SCREENING FOR NEURAL-TUBE DEFECTS
SIR,-We are conducting a pilot screening programme for neural-tube defects and find the comments by the Bishop of Durham (July 15, p. 148) and Dr Gould (July 29, p. 265) very timely. We agree that women should be made aware of the implications of screening before the first test, even though this takes considerable effort. Besides ethical issues, we have found that anxiety plays a major role in a woman’s choosing whether to participate in the screening programme. For a small, but significant, percentage of pregnant women, the anxiety appears so intense as to negate any possible benefits that testing might offer. There have been instances in our programme where an informed woman has elected to have screening done even though she would not agree to abortion. This has occurred because the physician felt that knowledge of a neural-tube defect would help to plan for delivery, including anticipation of possible breech presentation and consideration of csesarean section. Home deliveries would be strongly advised against, and fathers discouraged from attending in such circumstances. Foundation for Blood Research,
P.O. Box 426,
Scarborough, Maine 04074, U.S.A.
RELEVANCE OF HOMOEOPATHY
SIR,-It was surprising to read in your commentary from Westminster (July 15, p. 166) that the Postgraduate Medical Education Council feels that homoeopathy is not "of sufficient relevance to modern medical practice" to warrant financial support for training. "Modern medical practice" refers to all the possible effective and ethical ways in which a doctor manages his patients. To an open-minded observer homoe-
seems highly relevant to present-day medical practice in this sense. A large number of patients present in general practice and in hospital clinics with disorders not attributable to any demonstrable structural or biochemical lesion and which may come to be classified as "psychosomatic". Those whose symptoms include a disorder of the nasal mucosa, some pattern of vasomotor rhinitis, frequently finish their hospital pilgrimage at an allergy clinic. The ordinary resources of allergy study and management may be useful for some but the majority have no specific allergy or any other precisely determinable disease. When I followed up a few allergy-clinic failures who subsequently had homoeopathic treatment I was very favourably impressed. Some were no better but about half of them had become much fitter and happier people. There was more partial improvement than from any previous treatment. I would say that homoeopathy can be of very great value for this difficult group of patients and, from another point of view, offers the prospect of reducing the national drug bill for the tranquilisers and antihistamines which these patients generally receive. Allergy Clinic, Radcliffe Infirmary, Oxford OH2 6HE R. M. MORRIS OWEN
SCHOOL-TEACHERS AND HEALTH IN DEVELOPING COUNTRIES to congratulate Dr Ahmed (Aug. 5, p. his article on the potential contribution of primaryschool teachers to the health of a developing country, and to record some of our experience. In cooperation with the Government of Bangladesh, the Norwegian Red Cross is running a comprehensive health project, a thana health complex, for approximately 150 000 people living in Joydebpur Thana. In 1975, we appointed a female primary-school teacher and gave her some months’ training in basic pathology, hygiene, sanitation, nutrition, and family planning. A teaching programme was worked out, and she went out to the primary schools in the villages to give basic health education. We soon realised that her efficacy would be much increased if she started out by instructing the teachers, who would then carry the course to the classes. In cooperation with one or two of our paramedics, smallpox and B.C.G. vaccinations -are given. A-D vitamin capsules, anthelminthics, and scabies treatment are given according to needs (periodic deworming has a positive effect on nutritional status of ascaris-infected children1). The school tube-wells are kept in order, and a latrine building programme for the schools has been started. All eighty primary schools in the thana have now been covered, most of them several times. The programme is enthusiastically received by pupils and teachers alike, and the cooperation with school authorities has been very smooth. Steps are now being taken to introduce similar activities in other thanas in Bangladesh. We have not had the capacity to evaluate the programme scientifically. However, the children seem to be healthier and cleaner, and there has been a notable decline in the number of children treated for scabies and worms at our clinics. Although there has been some general improvement of the nutritional status at the same time in this area, it is tempting to give some credit to the school health programme as well. There are two limitations to such programmes: the greatest toll of child mortality is borne by preschool children, and some of the children who are worst off never come to school. However, the schoolchildren may have a positive influence on their families. Also, the programme is attractive in that it takes advantage of an already existing and effective infrastructure. Thus, I think the idea deserves to be an integral part of a comprehensive primary health care system in developing countries.
Krohgstötten Hospital, FINN WISLÖFF
Oslo, Norway 4. British Medical Journal, 1978, 5. Slessor,I. M. ibid. p. 716.
i, 668. 1.
C., Mithal, S., Arora, K. L., Tandon,
Lancet, 1977, ii, 108.