Serious morbidity associated with misuse of over-the-counter codeine–ibuprofen analgesics

To the Editor: The potential upper gastrointestinal morbidity associated with non-steroidal anti-inflammatory drug (NSAID) misuse is well known.1,2 Recently, Frei and colleagues3 provided an overview of the morbidity and patient characteristics relating to opioid–NSAID misuse; however, they did not identify those patients with NSAID enteropathy (NE). NE is thought to occur via NSAID-induced reduction of endogenous prostaglandin via inhibition of both cyclooxygenase (COX)-1 and COX-2. The result is altered mucosal integrity, which thereby allows exposure to noxious luminal contents leading to inflammation, erosion and ulcers.1 We underscore the importance of identifying this group of patients presenting with anaemia, hypoalbuminaemia, weight loss or abdominal pain that relates to NE.

The clinical presentation and small-bowel ulceration that is noted on investigations can often mimic Crohn’s disease.4 As the patient’s drug misuse is not immediately apparent, the diagnosis eludes the treating physician for some time, potentially at the expense of further morbidity from both ongoing medication misuse and the iatrogenic consequences of repeated presentations, investigations and medications that have been initiated to manage Crohn’s disease.

Within the Townsville Hospital v(a 460-bed tertiary referral centre for North Queensland), we have observed an increasing number of cases where patients covertly self-medicate with large doses (up to 20 tablets per day) of codeine–ibuprofen analgesics, taken mainly for codeine addiction, subsequently developing small-bowel abnormalities. We present three cases that highlight this problem (Box). In each of these cases, the NSAID use was not immediately apparent. A recent search on the Adverse Drug Reactions Advisory Committee database did not identify any reports of such patients. This may represent significant underreporting of the issue due to lack of physician awareness.

In mid-2010, the National Drugs and Poisons Schedule Committee implemented changes to how over-the-counter combination analgesics containing codeine can be accessed.5 Such medications must be accompanied by product and consumer medicine information, and a pharmacist must be involved at every sale to record the customer’s details. Despite these changes, there are still potential pitfalls, as there is no mechanism in place to stop patients from “pharmacy hopping”. It may be necessary to reschedule codeine as a prescription-only substance, and to create real-time databases of over-the-counter sales. While these drugs remain accessible over the counter, patients will continue to use them. Clinicians should therefore be vigilant for evidence of NSAID impact on the gastrointestinal tract.