Neomycin (Hansard, 6 February 1989)

§ Mr. Ashley

To ask the Secretary of State for Health (1) how many people are estimated to suffer burns or scalding accidents annually; what is the best estimate of those seriously burned or scalded and likely to have been thickly sprayed with neomycin;

(2) how many people are known to have been deafened by the use of neomycin sprays after being treated for burns or scalds; and what is the best estimate of the number at risk of being deafened in this way;

(3) when neomycin was first used in National Health Service hospitals in spray form; what Government safety health checks it had received prior to that date; for what purposes it was recommended; and what warnings of side effects were given;

(4) at what date neomycin was available to National Health Service hospitals; what Government safety health checks it had received before use within the National Health Service; for what purposes it was recommended; and what warnings of side effects were given;

(5) what is his best estimate of the number of people known to have been deafened by neomycin used in conventional form;

(6) when were the first research reports that neomycin could cause deafness; who they were by; and what action was taken by his Department to warn those using the drug;

(7) if he will set up an inquiry to investigate (a) the number of adults and children deafened by the use of neomycin sprays to treat burns and scalds, (b) the

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possibility of identifying them, (c) the possibility of giving publicity to the fact that, in some circumstances compensation may be possible, (d) the difficulties that people deafened in this way have in getting access to medical records and (e) the effectiveness of procedures which transmit information about the side effects of drugs;

(8) what information he has as to when research first established that compounds applied to the skin could be absorbed into the bloodstream and as to what action was taken to link this information to known hazards of drugs taken intravenously; and what action was taken by his Department to ensure that this information was known by those likely to treat burns.

§ Mr. Mellor

[holding answer 31 January 1989]: Medicines containing the antibiotic substance neomycin were introduced in the early 1950s. There was then no general statutory requirement for pre-marketing approval of the type introduced by the Medicines Act 1968. It is not now possible to be precise about the date of introduction or the conditions of marketing. Reports of ototoxicity (damage to the ear, including deafness) associated with injections of neomycin led to discussion in the medical literature in the early 1960s of the risks of deafness. The injectable forms were subjected in 1966 to the Therapeutic Substances Act (TSA) 1956. TSA control was more limited than the comprehensive system under the Medicines Act 1986. Its chief objects were to ensure purity and potency. The risk of ototoxicity associated with all forms of neomycin was reported by the later 1960s.

Over the period 1963 to 1988, 14 suspected cases of neomycin-associated deafness were reported to the Committee on Safety of Medicine (CSM) and its predecessor the Committee on Safety of Drugs (CSD). These reports derive from all formulations of neomycin. It is not meaningful to extrapolate from these reports. As with all prescription-only medicines, the decision in balancing the benefit of treatment of individuals against the risk of unwanted effects is a matter for clinical judgment. I am advised that clinical use of neomycin has become progressively selective with appreciation of the risks of ototoxicity, which the licensing authority (LA) and advisory bodies have played their part in fostering. Centrally available information is held on the number of hospital in-patient cases treated for burns and scalds. The latest available figure is an estimate of 11,190 for 1985, but there is no central information as to whether they were treated with neomycin.

Medicines containing neomycin are subject to all the normal prescription-only controls. Data sheets inform doctors of the risks of ototoxicity. Moreover, in addition to the control of the products, the substance neomycin itself is controlled under the Medicines (Control of Substances for Manufacture) Orders 1971 and 1985 (SI 1971/1200 and SI 1985/1403): Individual batches are tested by the National Institute for Biological Standards and Control.

The CSM issued a warning to all doctors in 1977: The association of deafness with the parenteral use of neomycin is well established. The Committee on Safety of Medicines have recently received reports of deafness following topical administration of aerosol preparations containing neomycin used in the treatment of extensive skin damage resulting from burns or other causes. The Committee urge the profession to report any case of ototoxicity which they suspect may have resulted from topical administration of aerosol or any other preparations containing neomycin or other antibiotics.

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The CSM issued a reminder in 1981 in the Current Problems publication to all doctors: The Committee on Safety of Medicines wishes to remind doctors that when otitis externa is treated topically with preparations containing chlorhexidine aminoglycoside antibiotics (eg neomycin, framycetin) or polymxins in patients who have a perforation of the tympanic membrane, there is an increased risk of drug-induced deafness. It is therefore important to ensure that there is no perforation in such patients before prescription of these preparations.

The LA reviewed in 1979–80 with advice from the Committee on Review of Medicines (CRM), some medicines with neomycin which had been on the market before the Medicines Act was brought into effect; were mainly anti-diarrhoea products; generally, the result was to limit permitted indications for use and require additional warnings in product literature of the products which remained licensed.

Other neomycin products are brought under scrutiny as part of the review of all pre-Act medicines.

The independent "British National Formulary" distributed by the Department to all NHS doctors and pharmacists contains explicit warnings.

Discussions have begun with the medical profession with a view to developing voluntary means of access to medical records. It could be counterproductive 1:o anticipate the outcome.

It is for individuals who consider that they may have been made deaf by the use of neomycin to take advice. It would be inappropriate to prejudice such advice or any proceedings which might arise by a general statement or by inquiry into numbers affected or by attempting to identify individuals, for which there is no feasible central mechanism.