ArticleTherapeutic advances in drug safety2021
Tramadol-induced hiccups: a case-noncase study in the European pharmacovigilance database.
Article in Therapeutic advances in drug safety, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
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Who cites it
4 citing papers in PubMed.
- Tramadol-Induced Persistent Singultus: A Case Report on Diagnosis, Mechanism, and Management.Clinical case reports · 2026Article
- Persistent Opioid-Induced Hiccups: A Case Report.Clinical case reports · 2025Article
- Risk Factors for Respiratory Depression Associated with Tramadol Based on the Global Pharmacovigilance Database (VigiBase).Pharmaceuticals (Basel, Switzerland) · 2024Article
- Alkalising agents in urinary tract infections: theoretical contraindications, interactions and synergy.Therapeutic advances in drug safety · 2022Article
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3 authors.
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No grant is acknowledged in the PubMed record.
Abstract
backgroundHiccups are usually benign and self-limiting, but can sometimes be persistent. If left untreated, they can provoke severe discomfort, and even death. Hiccups can be idiopathic, organic, psychogenic, and caused by drugs. Although some case reports have suggested a possible association between tramadol and hiccups, to our knowledge, no study has analyzed this possible relationship. The aim of this study was to analyze whether a disproportionate number of cases of hiccups are reported for tramadol in the EudraVigilance database.
methodsA case-noncase study was conducted to assess the association between hiccups and tramadol, calculating reporting odds ratios (RORs) from 1 January 1995 to 11 September 2020. Cases were selected using the preferred term 'Hiccups'. The noncases used as controls were all other adverse drug reaction reports recorded in EudraVigilance during the same period. Exposure was defined as exposure to tramadol among cases and noncases. To reduce the risk of confounding by indication, the RORs for tramadol compared with other opioids were obtained. Additionally, we performed a confirmatory analysis in the World Health Organization pharmacovigilance database, VigiBase
resultsThere were 3089 cases of hiccups in the 7,213,623 reports. Tramadol was involved in 50 cases. The ROR for tramadol exposure was 3.35 [95% confidence interval (CI) 2.53-4.43]. This association persisted when comparing tramadol with other opioids; ROR: 2.13 (95% CI 1.52-2.99). Disproportionality was also observed in VigiBase
conclusionOur study confirms, for the first time, a possible signal for a tramadol-hiccups association. Nevertheless, observational analytical studies are needed to confirm these results. PLAIN LANGUAGE SUMMARY: Evaluation of the relationship between the tramadol and the risk of hiccups
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