Adverse drug interactions involving common prescription and over-the-counter analgesic agents.

BACKGROUND: Eight analgesic preparations with approved indications for acute pain were among the top 200 drugs prescribed in the United States in 2006. In addition, an estimated 36 million Americans use over-the-counter (OTC) analgesics daily. Given this volume of use, it is not surprising that a number of drug interactions involving analgesic drugs have been reported. OBJECTIVES: This article examines the pharmacologic factors that enhance the clinical relevance of potential drug interactions and reviews the literature on drug interactions involving the most commonly used analgesic preparations in the United States. METHODS: A PubMed search was conducted for English-language articles published between January 1967 and July 2007. Among the search terms were drug interactions, acetaminophen, aspirin, ibuprofen, naproxen, celecoxib, NSAIDs, hydrocodone, oxycodone, codeine, tramadol, OTC analgesics, alcohol, ethanol, antihypertensive drugs, methotrexate, warfarin, SSRIs, paroxetine, fluoxetine, sertraline, citalopram, serotonin syndrome, MAOIs, and overdose. Controlled clinical trials, case-control studies, and case reports were included in the review. RESULTS: A number of case reports and well-controlled clinical trials were identified that provided evidence of the relatively well known drug-drug interactions between prescription/OTC NSAIDs and alcohol, antihypertensive drugs, high-dose methotrexate, and lithium, as well as between frequently prescribed narcotics and other central nervous system depressants. In contrast, the ability of recent alcohol ingestion to exacerbate the hepatotoxic potential of therapeutic doses of acetaminophen is not supported by either case reports or clinical research. Use of ibuprofen according to OTC guidelines in patients taking cardioprotective doses of aspirin does not appear to interfere with aspirin's antiplatelet activity, whereas chronic prescription use of ibuprofen and other NSAIDs may interfere. Low-dose aspirin intake appears to abolish the gastroprotective effects of cyclooxygenase-2-selective inhibitors, including celecoxib. There is evidence of other less well known and potentially clinically significant drug-drug interactions, including the ability of selective serotonin reuptake inhibitors to inhibit the analgesic activity of tramadol and codeine through inhibition of their metabolic activation, to induce serotonin syndrome when used chronically in the presence of high doses of tramadol through synergistic serotonergic action, and to increase the potential for gastrointestinal bleeding associated with NSAID therapy through additive or supra-additive antiplatelet activity. CONCLUSIONS: Considering the widespread use of analgesic agents, the overall incidence of serious drug-drug interactions involving these agents has been relatively low. The most serious interactions usually involved other interacting drugs with low therapeutic indices or chronic and/or high-dose use of an analgesic and the interacting drug.

Burning mouth syndrome. A retrospective analysis of clinical characteristics and treatment outcomes.

Burning mouth syndrome is a condition characterized by burning sensations of the oral cavity in the absence of physical abnormalities of the mucosa or a detectable underlying medical disorder. It is a multifactorial disorder with unclear etiology, affecting predominatly middle-aged women. Multiple approaches to treatment have been described in the literature, with few controlled clinical trials regarding their efficacy. The objectives of this retrospective study were to: 1. determine the epidemiologic characteristics of BMS patients referred to an oral medicine practice; 2. determine if BMS classification correlates with response to treatment; 3. determine the efficacy of a variety of known therapies for BMS. A database was constructed from the charts of 150 consecutive patients diagnosed with BMS; and these charts were reviewed. Patients were classified according to previously published criteria for BMS. Presumed etiologies were grouped into depression/anxiety-associated; hematinic deficiencies, including iron, folate and vitamin B complex; oral habits: and idiopathic BMS. Treatment approaches were divided into seven categories: soft desensitizing appliance; tricyclic antidepressants (TCA); benzodiazepines (BZD); topical analgesics; hematinic supplements; habit awareness counseling; and multi-modal therapy (combining two or more of the above). Improvement was recorded using a zero to 100% VAS scale and classified as no relief (0%); mild (0-40%); meaningful/moderate (41-80%); and profound relief (81-100%). Burning mouth syndrome without any identifiable cause (idiopathic) was diagnosed in 33 patients (46.6%). Patients were followed up at one month (4 weeks) after the initial visit. Nine patients (12.7%) reported profound relief; 17 patients (23.9%) reported meaningful relief; 39 patients (54.9%) reported mild relief. This retrospective review showed no significant correlation between classification of BMS and response to therapy. The most effective treatment modalities were habit awareness, followed by TCAs.