DI-024 Off-label use of gabapentin and pregabalin in a tertiary hospital

Abstract

BackgroundGabapentin and pregabalin are two GABA analogues, example of an evergreening strategy. Both have been associated with a markedly off-label use.PurposeTo describe the extent and nature of the off-label use of gabapentin and pregabalin.Material and methodsProspective observational study performed in a tertiary hospital. We included patients being treated with gabapentin or pregabalin at any time between June and August 2014. The variables collected were: sex, age, drug, therapeutic indication, dose and cost per patient-month (according to retail prices). These data were used to describe the rate and nature of the overall use and off-label use by drug. Data were collected through review of medical records and by electronic pharmacy refill records. Statistical analysis was performed using SPSS Statistics 20.0.ResultsSixty-five patients (54% male, mean age 60 ± 14 years) were included. Eighteen (28%) were being treated with gabapentin and 47 (28%) with pregabalin. The overall off-label use was 43% (28 patients), with no differences between the drugs (44% gabapentin and 43% pregabalin). The off-label use was related to the therapeutic indication (25 patients) or the dose (3 patients). The off-label indications for gabapentin were: central neuropathic pain (6), subacute or chronic low back pain (3), generalised anxiety disorder (3) and refractory visceral pain (1). The off-label indications for pregabalin were: subacute or chronic low back pain (6 patients), fibromyalgia (5), and essential tremor (1). The average cost per patient-month was €25 ± 11 for gabapentin and €156 ± 65 for pregabalin.ConclusionGabapentin and pregabalin are often prescribed for off-label use. Despite having failed to demonstrate clinically relevant differences over gabapentin, pregabalin holds a high prescription rate with consequent extra costs for the hospital, representing an area in which rational drug use could be promoted.ReferenceRadley DC, Finkelstein SN, Stafford RS. Off-label prescribing among office-based physicians. Arch Intern Med 2006;166:1021–6No conflict of interest.

A snapshot of the prescribing patterns and off‐label use of gabapentinoid agents in tertiary care: a retrospective, cross‐sectional, descriptive study

“…Approximately one in 10 patients had their gabapentinoid therapy discontinued during their admission. This rate is similar to that reported by Gingras et al 13 There are reports of withdrawal symptoms following abrupt discontinuation of these agents. 22 Ceasing abruptly can result in anxiety, insomnia, headache, sweating, nausea and diarrhoea.…”

“…Such use has been reported by other researchers. 12,13 The high incidence of off-label prescribing noted in this study also raises issues related to the costs incurred by the patient when their care is transferred to primary care, as only approved indications are reimbursed under the Pharmaceutical Benefits Scheme (PBS). Legally, a private prescription would be required for an off-label indication, otherwise supply would be considered fraudulent if written by their General Practitioner on a PBS prescription.…”

“…Patterns and predictors of off-label use of gabapentinoids have been examined using both prospective and retrospective, descriptive, cross-sectional study designs. 12,13 Given the extensive use for a range of indications and the potential for harm, an assessment of the prescribing patterns of gabapentinoids within the Hunter New England Local Health District (HNE LHD) has the potential to inform optimal patient management.…”

Gabapentinoids: pharmacokinetics, pharmacodynamics and considerations for clinical practice

“…2,3 Off-label use includes management of a wide range of conditions such as bipolar disorder, complex regional pain syndrome, attention deficit disorder, restless legs syndrome, periodic limb movement, sleep disorders, headaches, alcohol withdrawal syndrome, chronic back pain, fibromyalgia, visceral pain and acute postoperative pain. 4,5 The rate of new prescriptions is increasing and tripled in England from 2007 to 2017. 6 Pregabalin prescriptions in England increased from 2.7 million scripts in 2013 to 7 million scripts in 2018.…”

Biological rationale and potential clinical use of gabapentin and pregabalin in bipolar disorder, insomnia and anxiety: protocol for a systematic review and meta-analysis

“…8 Gabapentin has a long history of off-label prescription. 9 Between 1998 and 2000, a study involving 105 Medicaid patients who were prescribed gabapentin found that 95% of prescriptions had been for off-label indications. 10 A number of these indications were for psychiatric illness, including bipolar disorder (10% of all prescriptions in the study) and anxiety disorders.…”