Concomitant Prescription Research Articles

English

Non Steroidal anti-inflammatory Drugs (NSAIDs) are most commonly prescribed drugs constituting more than 20% of all drug prescriptions. Prescription pattern study of NSAID was conducted in Medicine OPD of a rural teaching hospital with the objective of analyzing prescribing trend of NSAIDs, to evaluate co-prescription of Gastro-protective agents (GPAs) with NSAIDs and to determine number of prescribed NSAIDs falling within Drug utilization (DU) 90% segment. Overall 200 NSAID prescriptions were analysed. Prevalence of NSAID prescription was 25.71%. Paracetamol (36%) was the commonest drug prescribed. In general non-selective NSAIDs were more commonly prescribed (79.5%) and selective COX-2 inhibitors were least prescribed (1%). High prevalence of nimesulide prescription (19.5%) was a significant finding. Co-prescription of GPAs was high (61%). Four drugs (paracetamol, diclofenac, nimesulide and aceclofenac) fall within DU90% segment. In general prescription pattern requires further rationalization of NSAID usage as more number of drugs constitutes DU90% segment. KEY WORD: Prescription pattern, NSAID, DU90%, GPAs co-prescription. INTRODUCTION: The treatment of pain and inflammation is an important area of therapeutics. Over the past two decades, non steroidal anti-inflammatory drugs (NSAIDs) have played a central role in these indications. NSAIDs constitute the largest single group of drugs used worldwide, constituting more than 20% of all drug prescriptions 1 . In India over 400 formulations of NSAIDs are marketed, resulting in wide spread exposure of patients to this class of drugs and its adverse effects 2 . For all these reasons, studies that evaluate the pattern, extent and frequency of NSAID prescriptions are valuable. The demonstration of two unique isoforms of cyclooxygenase (designated as COX-1 and COX- 2) has led to a greater understanding of the mechanisms of action of NSAIDs and their toxicity 3 . The beneficial anti-inflammatory effect of the NSAIDs had been attributed to inhibition of COX-2, while the gastrointestinal (GI), renal and anti-platelet adverse effects were attributed to COX-1 inhibition 4 . Prescription pattern of NSAID changed frequently over a period of time. With the introduction of the selective COX-2 inhibitors, it has been suggested that they may be more cost-effective because of their improved GI tolerability and a reduction in concomitant prescription of antiulcer agents. This has led to an increase of almost 50% in the total number of NSAID prescriptions dispensed, with COX-2 drugs accounting for two thirds of this increase 3 . Before withdrawal of Rofecoxib, the prescriptions of COX-2 selective inhibitors had accounted for 37% of the total NSAID prescriptions dispensed. After its withdrawal in 2004, following the emergence of evidence of increased cardiovascular morbidity in the APPROVe (Adenomatous Polyp Prevention on Vioxx) study, COX-2 inhibitors represented less than 16% of the

Adherence, Persistence, and Predictors Associated with Early Niacin Termination

Background: Niacin is the most effective therapy currently available to increase high-density lipoprotein cholesterol. However, adherence to niacin may be limited by a number of factors and it is important to characterize who is likely to discontinue the medicine. Objective: To measure adherence and persistence to niacin, estimate the influence of niacin dose on adherence, and identify factors associated with early termination of niacin. Methods: This retrospective study estimated adherence to niacin by calculating the medication possession ratio, persistence, number of refills, and termination proportion in a large, deidentified US health claims database consisting of 42,685 insurance-carrying adults who were new users of niacin. Results: We identified 29,801 new users of niacin who were not taking statins or fibric acid, 12,298 new users of niacin plus statin, 441 new users of niacin plus fibric acid, and 145 new users who initiated all 3 agents. Persistence was lowest among individuals taking less than 1 g/day and was highest among those taking niacin plus fibric acid plus statin (5.10 vs 7.17 months, respectively). However, lower niacin dose was associated with greater adherence, regardless of statin use. Termination of niacin within 1 year of initiation was significantly associated with being female or having 1 of the following conditions: peripheral vascular disease, chronic pulmonary disease, diabetes mellitus, rheumatic disease, or liver disease. Increased age, taking niacin in combination with a statin, or taking drugs from 2 or more concomitant prescription medication classes were significantly associated with a reduced likelihood of termination within 1 year. Conclusions: We observed relatively high adherence rates to niacin; however, most patients failed to persist with use of the drug beyond 7 months.

AB0810-PC Even short term treatment with nsaids may be unsafe: the feasibility of replacing the nsaid prescription with regular paracetemol

BackgroundThe NSAID prescription is prevalent in patients seen in primary care with rheumatic and musculoskeletal problems (1). New evidence suggests that there is a significant increase in the risk of...

AB0673 Development of identification algorithm for systemic lupus erythematosus diagnosis in the korean national health insurance claims database

BackgroundHealth insurance claims data are widely used for researchers to describe health care utilization, patterns of care, disease prevalence, drug and disease outcomes, and cost of care. In South Korea,...

Bleeding events and activated partial thromboplastin time with dabigatran in clinical practice

BackgroundDabigatran has demonstrated promising results for the prevention of strokes in patients with non-valvular atrial fibrillation (NVAF). However, there have been episodes of major bleeding, especially in elderly patients or those with renal dysfunction. The purpose of this study was to retrospectively examine the relationship between the bleeding events and activated partial thromboplastin time (APTT) values under dabigatran usage in the everyday clinical practice. Moreover, we investigated which factors would contribute to the APTT values. Methods and resultsA total of 139 NVAF patients (112 men, 65±11 years) were included. We evaluated the influence of the putative etiological variables and the bleeding score, HAS-BLED score, on APTT values: age greater than 70 years, renal function, gender, dose of dabigatran, and the concomitant prescription of a P-glycoprotein inhibitor. There were 50 patients with an age of ≥70 years (36.0%). A P-glycoprotein inhibitor was administered in 18 patients. During the observation period (median 120 days) there was 1 episode of asymptomatic cerebral infarction. There were no intrinsic major bleeding events, however, 11 patients had minor hemorrhagic events. The results of the APTT measurements exhibited a variety of values both among inter- and intra-individuals. On multivariable analysis, significant associations were found between the following risk factors and the APTT values: creatinine clearance, dose of dabigatran, and concomitant use of a P-glycoprotein inhibitor. The minor bleeding events did not correlate with the APTT values, nor HAS-BLED score. ConclusionsThe APTT values became prolonged under dabigatran usage and exhibited a remarkable diversity. Although major bleeding did not occur unless APTT was prolonged excessively, minor bleeding arose irrespective of the APTT values even within the range of the APTT values not exceeding 80s.

Osteoarthritis guidelines: a progressive role for topical nonsteroidal anti-inflammatory drugs

Current treatment guidelines for the treatment of chronic pain associated with osteoarthritis reflect the collective clinical knowledge of international experts in weighing the benefits of pharmacologic therapy options while striving to minimize the negative effects associated with them. Consideration of disease progression, pattern of flares, level of functional impairment or disability, response to treatment, coexisting conditions such as cardiovascular disease or gastrointestinal disorders, and concomitant prescription medication use should be considered when creating a therapeutic plan for a patient with osteoarthritis. Although topical nonsteroidal anti-inflammatory drugs historically have not been prevalent in many of the guidelines for osteoarthritis treatment, recent evidence-based medicine and new guidelines now support their use as a viable option for the clinician seeking alternatives to typical oral formulations. This article provides a qualitative review of these treatment guidelines and the emerging role of topical nonsteroidal anti-inflammatory drugs as a therapy option for patients with localized symptoms of osteoarthritis who may be at risk for oral nonsteroidal anti-inflammatory drug-related serious adverse events.

Comparison of deliverable IMRT and VMAT for spine metastases using a simultaneous integrated boost

To effectively treat spine metastases, significant dose must be delivered to regions surrounding the spinal cord. We present a study comparing both step-and-shoot intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques to deliver a concomitant hypofractionated prescription dose to the diseased region and to the involved vertebrae. Seven-field IMRT and a single arc VMAT were inversely planned on five (two cervical and three thoracic) spinal metastatic patients. Planning target volumes PTVm (macroscopic) and PTVe (elective involved vertebrae) and associated organs at risk were localised. Mean doses of 35 Gy to PTVm and 20 Gy to PTVe were prescribed in five fractions. Dose statistics, estimated delivery time and results of verification using Delta(4) (ScandiDos, Uppsala, Sweden) were compared. Deliverable plans were achieved with both IMRT and VMAT. The coverage to PTV was similar for both IMRT and VMAT (p=0.5) and the dose to the regions adjacent to the spinal cord was 1% higher with VMAT (p=0.04). The mean delivery time for VMAT was 3.5 min compared with 10.5 min for IMRT. Fewer monitor units were required to deliver IMRT than to deliver VMAT. The median (range) percentage of measured points with a γ-index <1 with 3%/3 mm was 100 (99.9-100)% for IMRT and 100 (88.5-100)% for VMAT. Both VMAT and IMRT can deliver the concomitant hypofractionated regime proposed, and both offer different benefits in dose delivery. IMRT is currently preferred for its superior pre-treatment verification results and shorter planning times. This study explores the feasibility of delivering tumouricidal doses of radiation to metastatic spine disease in the vicinity of the spinal cord.

Role of Complementary and Alternative Medicine in Cardiovascular Diseases

Role of Complementary and Alternative Medicine in Cardiovascular Diseases

Clinically significant interactions between antiretroviral and co-prescribed drugs for HIV-infected children: profiling and comparison of two drug databases

BackgroundDrug–drug interactions are an important therapeutic challenge among human immunodeficiency virus-infected patients. Early recognition of drug–drug interactions is important, but conflicts do exist among drug compendia on drug interaction information. We aimed to evaluate the consistencies of two drug information resources with regards to the severity rating and categorization of the potential interactions between antiretroviral and co-prescribed drugs.MethodsWe reviewed the case files of human immunodeficiency virus-infected children who were receiving treatment at the human immunodeficiency virus (HIV) clinic of the Lagos University Teaching Hospital, Idi Araba, between January 2005 and December 2010. All of the co-prescribed and antiretroviral drug pairs were screened for potential interactions using the Medscape Drug Interaction Checker and the Monthly Index of Medical Specialties Interaction Checker. Drug–drug interaction (DDI) severity and categorization were rated on a scale of A (no known interaction); B (minor/no action needed); C (moderate/monitor therapy); D (major/therapy modification); and X (contraindicated/avoid combination).ResultsA total of 280 patients were at risk of 596 potential DDIs. The databases showed discrepancies, with Medscape database identifying 504 (84.6%) and USA MIMS database identifying 302 (50.7%) potential DDIs. Simultaneous identification of DDIs by both databases occurred for only 275 (46.1%) listed interactions. Both databases have a weak correlation on the severity rating (rs = 0.45; P < 0.001). The most common DDIs identified by the databases were nevirapine and artemisinin-based combination therapy (170; 28.5%), nevirapine and fluconazole (58; 9.7%), and zidovudine and fluconazole (55; 9.2%). There were 272 (45.6%) interaction severity agreements between the databases.ConclusionDiscrepancies occurred in DDI listings between Medscape and USA MIMS databases. Health care professionals may need to consult more than one DDI information database to ensure safe concomitant prescribing for HIV patients.

Trends in psychotropic drug prescribing in Norwegian nursing homes from 1997 to 2009: a comparison of six cohorts

Psychotropic drugs are extensively prescribed for the treatment of neuropsychiatric symptoms, despite modest efficacy and severe side effects. We examined trends in psychotropic drug prescribing in Norwegian nursing homes from 1997 to 2009, in order to gain insight in practice development. The study is a secondary data analysis of six cross-sectional nursing home studies conducted between 1997 and 2009. Patients aged >65 years were included. We compared the prevalence of psychotropic drugs (antipsychotics, anxiolytics, hypnotics, and antidepressants). Associations between prescription of psychotropics, and patients' age, gender, type of ward, and year of data collection were examined by univariate analysis and logistic regression. Altogether, 7 661 patients (mean age 85.2 years, 72.6% women) were included. Prevalence of all psychotropic drugs combined increased from 57.6% to 70.5%, anxiolytics from 14.9% to 21.9%, hypnotics from 14.5% to 22.9%, and antidepressants from 31.5% to 50.9%. Prevalence of antipsychotics varied between extremes 21.1% and 25.6%. Less prescribing of older drugs was exceeded by an increase in newer drug types. Concomitant prescribing of two or more psychotropic drugs increased from 21% to 33%. Predictors of psychotropic drugs were female gender (except antipsychotics), as well as age <80 years, and residency in special care units (except hypnotics). Prescribing of psychotropic drugs in nursing homes has increased considerably, especially regarding antidepressants. Explanations for this trend need to be further explored.

Antidepressant switching patterns in the treatment of major depressive disorder: a General Practice Research Database (GPRD) Study

To investigate switching patterns of major antidepressant treatments and associated factors in a primary care adult population with major depressive disorder (MDD) using data from the General Practitioner Research Database (GPRD). A retrospective cohort study was conducted using the GPRD. The study included patients with MDD, aged [18-70], with a new prescription for amitriptyline, citalopram, escitalopram, fluoxetine, paroxetine, sertraline or venlafaxine between January 1, 2001 and September 30, 2003 and having no antidepressant prescription in the 6 months preceding index date. Switching of antidepressant treatment was defined as a prescription of a different antidepressant among all available marketed antidepressant treatment at this time (no restriction of compound) from 1 month before up to 2 months after the calculated end of the previous antidepressant treatment. Survival analysis techniques were used to describe switching of antidepressant and time to switch. Profiles of switchers were described and by-treatment analyses performed. Data from over 59,000 patients showed that 16% switched antidepressants. Seventy-two per cent of switches appeared within 3 months after treatment initiation. Within switchers, median time to switch was 53 days. Switching patients had generally a more severe psychiatric profile, including more previous episodes of depression or other psychiatric disorders. They also had a higher proportion of concurrent psychiatric disorders (especially anxiety) and concomitant prescription of anxiolytics or hypnotics. Patients initially prescribed amitriptyline were almost twice as likely to switch (27%) as patients prescribed venlafaxine (17%) or an SSRI (15%). This population-based study confirmed that antidepressant switch is more likely to occur within the first 3 months of treatment and in patients with a more severe psychiatric profile. A particular attention paid to these patients within the early phase of treatment may therefore help to improve their management.

Traditional Chinese medicine speeds-up humerus fracture healing: Two case reports

Two cases illustrate the potential benefit of traditional Chinese medicine (TCM) treatments on speeding-up proximal humeral fracture healing. The cases include two patients with traumatic right proximal humerus closed fracture, one who fell down while standing on a chair and the other hit by a moped. Alternative treatments had been applied to restore humerus fracture. They were treated with the same modality by acupuncture on LI4, LI10, LI1, LI15, LI16 and SI9, with occasional electroacupuncture at LI4 and LI16, as well as concomitant herbal formula powder prescription named "Zhèng Gŭ Zĭ Jīn Dān". Within 2 months treatment, both patients seemed to have speed-up bone healing. The Constant Score increased from 9 to 42 and 36, before and after acupuncture therapy. To our experience, the old patients' fracture had speed-up healing while under TCM treatments. This might hint that TCM treatments not only play a role in pain control, but also accelerate bone healing for certain fracture cases. Long-term follow-up and future experimental studies are warranted to examine the efficacy of TCM treatments for healing bone fracture in the elderly.

Prospective, randomized, double‐blind, clinical evaluation of Aloe vera Barbadensis, applied in combination with a tongue protector to treat burning mouth syndrome

The aim of this study was to evaluate the efficacy of aloe vera (AV) applied in combination with a tongue protector, comparing this with a placebo. A total of 75 patients with burning mouth syndrome (BMS) were divided into three groups randomly: Group I (tongue protector three times a day), Group II (tongue protector and 0.5ml AV at 70% three times a day) and Group III (tongue protector and 0.5ml placebo three times a day). Symptoms were evaluated by visual analogue scale (VAS), while patient psychological profiles were assessed using the Hospital Anxiety-Depression scale and their quality of life using the Oral Health Impact Profile 49 (OHIP-49). Treatment continued for 3months. Visual analogue scale pain values improved for all three study groups but without statistically significant differences between the groups (P=0.210). Regarding quality of life, no significant differences were found between groups with the exception of the OHIP-49 score for handicap. The overall clinical improvement was greater for Group II, with a difference almost reaching significance. The concomitant prescription of tongue protector and AV is effective for treating patients with BMS.

Correlates of Potentially Inappropriate Prescriptions of Benzodiazepines among Older Adults: Results from the ESA Study

ESA study data were paired with Quebec medical and pharmaceutical services records to document potentially inappropriate benzodiazepines (Bzs) prescriptions among community-dwelling adults aged 65 and older. Results indicate that 32 per cent of respondents took a mean daily dose of 6.1 mg of equivalent diazepam for, on average, 205 days per year. Almost half (48%) of Bzs users received a potentially inappropriate benzodiazepine prescription at least once during the year preceding the survey. About 23 per cent received at least one concomitant prescription of a Bz and another drug that could result in serious interaction. In addition, individuals aged 75 and older were more likely to receive Bzs for a longer period of time than those aged 65-74. Number of pharmacies used was associated with inappropriate Bzs prescriptions. Our results argue in favour of a more integrated health services system, including a regular review of older adults' drug regimens.

Intravitreal chemotherapy for vitreous disease in retinoblastoma revisited: from prohibition to conditional indications

BackgroundTumour control of vitreous seeds remains challenging owing to their resistance to radiation and systemic chemotherapy.ObjectiveTo describe the short-term efficacy of intravitreal melphalan for vitreous disease in retinoblastoma using a...

Prevalence of Concomitant Oral Antipsychotic Drug Use Among Patients Treated With Long-Acting, Intramuscular, Antipsychotic Medications

Long-acting injectable (LAI) antipsychotic drugs are viewed as monotherapeutic alternatives to oral medications to promote medication adherence, but there have been no descriptive studies of concomitant use of oral and LAI medications. A list of all patients receiving services from the Connecticut Mental Health Center from July 1, 2009, to June 30, 2010, was obtained from center administrative records, and those carrying an initial intake diagnosis of schizophrenia or schizoaffective disorder were identified. All team leaders were approached, and all clinicians were asked to identify patients on their case load prescribed LAIs during the time interval above. Also, all internal and external pharmacy orders were reviewed. Concomitancy was defined as simultaneous oral and LAI antipsychotic use at any time from July 1, 2009, to June 30, 2010. Data were culled from the medical records using a form (available on request) that recorded current LAI antipsychotic, reasons for LAI use, length of time on LAI, monthly dosage, and all concomitant oral antipsychotics, antidepressants, and anxiolytic agents. Among 124 patients on LAI medications, 57 (46%) received concomitant oral and LAI antipsychotics: 27 (47%) were prescribed LAI haloperidol, 19 (33%) LAI fluphenazine, and 11 (19%) risperidone microspheres. Logistic regression showed greater use of oral antipsychotic for both Hispanic ethnicity (odds ratio, 3.8; 95% confidence interval, 1.3-10.8) and alcohol abuse/dependence (odds ratio, 6.5; 95% confidence interval, 1.3-31.9), with no significant differences on other variables. There were no significant differences between LAI agents in rates of use of concomitant oral antipsychotic, anticholinergic, sedative/hypnotic, or mood stabilizer. Patients were more likely to be prescribed concomitant oral preparations of their LAI agent than another oral antipsychotic. Higher dosing of LAI treatments was associated with a significantly greater likelihood of use of oral psychotropics and anticholinergics. Almost one half of patients prescribed LAI antipsychotics receive oral antipsychotics and other oral psychotropics. This challenges the notion that LAIs are used as monotherapy in real-world settings. Concomitant oral and LAI antipsychotic prescriptions may represent a common practice of polypharmacy that merits further investigation.

Observations of hydrocodone co-prescriptions and non-reported prescription medications in a population of those with chronic pain

While efficacious for the treatment of chronic pain, the use of opioid analgesics is associated with a high overdose risk, concomitant use of non-prescribed drugs, and diversion. Among patients with chronic pain prescribed hydrocodone, the prevalence of illicit drug use and prescription drug misuse is as high as 24%. Another issue with the use of opioid analgesics is the danger of adverse drug events due to drug-drug interactions. The purpose of this study was to understand the relationship of hydrocodone with concomitant prescriptions and non-prescribed medications in order to identify and minimize health risks.

A Case of Intention Tremor Induced by the Combination of Aripiprazole and Lamotrigine

To the Editor: In patients with chronic disabling psychiatric conditions in whom many therapeutic interventions have been implemented, augmentation and combination therapies are commonly used to improve the outcome. The number of visits during which a psychotropic medication was prescribed increased from 32.73 million to 45.64 million in less than 10 years in office-based physician practices in the United States.1 Here, we report a case of intention tremor induced by a combination of aripiprazole and lamotrigine. Case report. Ms A was a 60-year-old white woman with a 6-year history of DSM-IV major depressive disorder and generalized anxiety disorder and no history of psychiatric hospitalizations. Her past medical and surgical history was significant for type 2 diabetes mellitus, above-knee amputation, hysterectomy, and arthritis. Her family history was negative for psychiatric disorders. She denied smoking, drinking alcohol, or using illegal drugs. Multiple medications were tried before Ms A became stable on treatment with lamotrigine 300 mg/d for several years. Although the patient was stable, there was room for improvement in her symptoms, and in February 2011, aripiprazole 5 mg/d was added as an augmenting agent. The patient's symptoms improved, and she became socially active, volunteering at the local hospital and spending time with her friends. However, 2 months after starting aripiprazole treatment, the patient developed a disabling intention tremor in her hands, head, and jaw. Lamotrigine was tapered off slowly with no deterioration of her mood and complete resolution of her tremor. Moreover, she reported maintaining an active social life at 3-, 6-, and 12-month follow-up. Our patient was prescribed both lamotrigine and aripiprazole for major depression, and she had a therapeutic response, but we noted an interesting adverse effect that can be attributed only to the concomitant prescription of these medications. Aripiprazole, like other atypical antipsychotics, displays antagonistic action at serotonin-2A (5-HT2A) receptors. However, it differs from other antipsychotics in that it is a partial agonist at dopamine-2 receptors and 5-HT1A receptors.2 Both cytochrome P450 (CYP) 3A4 and the polymorphic enzyme CYP2D6 are involved in the metabolism of aripiprazole to its main metabolite dehydroaripiprazole.3 On the other hand, lamotrigine is metabolized predominantly by glucuronic acid conjugation, mainly by UDP-glucuronosyltransferase 1A4 with the inactive 2-N-glucuronide conjugate as the major metabolite.4 Literature suggests that lamotrigine increases the concentration to dose ratios of aripiprazole by 51%.5 According to the Naranjo Adverse Drug Reactions Probability Scale, the intention tremor reaction reported in this case can be classified as a “probable” association between the combination of aripiprazole and lamotrigine and the side effect.6 The onset of the clinical adverse effect is consistent with the administration of the drugs together, and the effect was not present when either drug alone was given to the patient. To our knowledge, this is the first report of a clinical interaction of aripiprazole and lamotrigine that resulted in intention tremor. We anticipate that many more such cases will surface as combination treatment becomes a norm in the treatment of psychiatric illnesses. Clinicians should be vigilant against this problem and should be ready to adjust treatment with discontinuation of either medication if faced with such an adverse effect in their patients.

Analysis of the valproic acid-meropenem interaction in hospitalised patients

IntroductionPublished data demonstrate a serious interaction between valproic acid and meropenem. However, recommendations about the management of concomitant treatment are contradictory; some experts recommend closer monitoring of valproic acid serum concentrations and others recommend avoiding concurrent therapy. The purpose of this study is to critically analyse the interaction and to evaluate the impact of pharmaceutical intervention in the use of these drugs in hospitalised patients. Material and methodsStudy of the concomitant prescription of valproic acid and meropenem in a general hospital of 1080 beds divided in to two periods; the first period was retrospective and observational and it was followed by a prospective period involving pharmaceutical intervention. The prescription habits between both periods were compared. ResultsA total of 26 patients received concurrent treatment with valproic acid and meropenem (13 per period) and none of them maintained therapeutic serum levels of the antiepileptic drug. Pharmaceutical intervention modified prescription habits, reducing by half the number of days of concomitant treatment, changing the antibiotherapy and/or monitoring serum concentrations more often. ConclusionsThe interaction between valproic acid and meropenem is serious, especially because of the dramatic decrease in the antiepileptic serum concentrations. The concomitant use of both drugs should be avoided, replacing the antibiotherapy empirically, or according to the resistance profiles of the microorganism and maintaining the same the anti-epileptic treatment.

Risk of herpes zoster in patients prescribed inhaled corticosteroids: a cohort study

BackgroundLittle is known concerning risk factors for herpes zoster in the general population. We hypothesised that inhaled corticosteroids (ICS) are a risk factor for herpes zoster especially among users of inhibitors of cytochrome P450 enzymes involved in their metabolism.MethodsWe identified a cohort of adult users of respiratory medications in the General Practice Research Database and carried out a nested case control analysis of inhaled corticosteroid use among 8900 new cases of herpes zoster and 88032 controls matching on age and calendar time.ResultsThe adjusted odds ratio for the relationship between current use of ICS and the occurrence of herpes zoster was 1.00 (95% confidence interval (CI), 0.94-1.07). There was no increase in risk of herpes zoster even at higher ICS doses; odds ratio 1.05 (95% CI, 0.96-1.14). Among subjects with concomitant prescriptions for an ICS and an inhibitor of cytochrome P450 3A4, the point estimate for the association between herpes zoster and the use of higher doses of inhaled corticosteroids was 1.23 (95% CI, 0.81-1.88).ConclusionsThe use of inhaled corticosteroids, even at high doses and in conjunction with inhibitors of their metabolism, was not a significant risk factor for the occurrence of herpes zoster in adults.