Letters

Gastrointestinal bleeding is common

The annual incidence of end stage renal disease, another possible adverse effect of prolonged exposure to analgesics and non-steroidal anti-inflammatory drugs, is of the order of 100 per million people,³ and, according to the data from two case-control studies, analgesic drugs account for 11-13% of all these cases.^{4 5} The annual incidence of agranulocytosis (excluding patients receiving antineoplastic chemotherapy or radiotherapy) is 4.7 per million people, and that of aplastic anaemia (same criteria) is 2.0 per million.⁶ According to a study carried out in the Netherlands, the incidence of severe anaphylaxis from all causes is 13.5 per million per year; drugs in general account for 42% of these cases, and analgesic and anti-inflammatory drugs in particular account for 26% of all cases.⁷ Preliminary data from a study being carried out in Barcelona suggest that the annual incidence of severe non-viral hepatitis is 5-10 cases per million people.

At least a quarter of all episodes of upper gastrointestinal bleeding are attributable to non-steroidal anti-inflammatory drugs.¹ The figures we quote show that upper gastrointestinal bleeding is by far the most common potential adverse effect of analgesics and non-steroidal anti-inflammatory drugs. Therefore, the risk of gastrointestinal bleeding associated with each of these drugs should be one of the main factors determining which drug to use.

Professor of clinical pharmacology Assistant professor of clinical pharmacology Associate professor of clinical pharmacology Unit of Clinical Pharmacology, Autonomous University of Barcelona, Servei de Farmacologia Clinica, CSU Vall d'Hebron, 08035-Barcelona, Spain

Joan-Ramon Laporte, Xavier Vidal, Xavier Carne 

1. Bateman DN, Kennedy JG. Non-steroidal anti-inflammatory drugs and elderly patients. BMJ 1995;310:817-8. (1 April.) [Free Full Text]
2. Laporte JR, Carne X, Vidal X, Moreno V, Juan J. Upper gastrointestinal bleeding in relation to previous use of analgesics and non-steroidal anti-inflammatory drugs. Lancet 1991;337:85-9. [Medline]
3. Registre de Malalts Renals de Catalunya. Deu anys del Registre de Malalts Renals de Catalunya. Butlleti Epidemiologic de Catalunya 1994;15:165-7,173-6.
4. Morlans M, Laporte JR, Vidal X, Cabeza D, Stolley PD. End-stage renal disease and non-narcotic analgesics: a case-control study. Br J Clin Pharmacol 1990;30:717-30. [Medline]
5. Perneger TV, Whelton PK, Klag MJ. Risk of kidney failure associated with the use of acetaminophen, aspirin, and non-steroidal antiinflammatory drugs. N Engl J Med 1994;331:1675-9. [Abstract/Free Full Text]
6. Kaufman DW, Kelly JP, Levy M, Shapiro S. The drug etiology of agranulocytosis and aplastic anemia. New York: Oxford University Press, 1991.
7. Van der Klauw MM, Stricker BHC, Herings RMC, Cost WS, Valkenburg HA, Wilson JHP. A population based case-cohort study of drug-induced anaphylaxis. Br J Clin Pharmacol 1993;35:400-8. [Medline]