Tizanidine-induced acute severe cystitis in a female taking famotidine

Coadministration of tizanidine and ciprofloxacin: a retrospective analysis of the WHO pharmacovigilance database

PURPOSE

Tizanidine, an alpha-adrenergic substance with antinociceptive and antihypertensive effects, is extensively metabolized via cytochrome P450 (CYP) 1A2. Therefore, coadministration with potent CYP1A2 inhibitors, such as ciprofloxacin, is contraindicated. However, both drugs are broadly utilized in various countries. Their concomitant use bears an inherent high risk for clinically significant symptoms, especially in multimorbid patients experiencing polypharmacy. This study aims to investigate the impact of coadministration of tizanidine and ciprofloxacin using real-world pharmacovigilance data and to raise awareness of this potentially underestimated safety issue.

METHODS

We conducted a retrospective study including Individual Case Safety Reports (ICSR) registered until March 1, 2017, in the World Health Organization (WHO) global database. Demographic data, drug administration information, the course of the adverse drug reaction (ADR), its severity, and outcomes were analyzed for cases reporting ciprofloxacin comedication.

RESULTS

In 91 (2.0%) of the identified 4192 worldwide ICSR on tizanidine, coadministration of ciprofloxacin was reported. Most of the patients were female (n = 59, 64.8%) with a median age of 54 years (range 13-85 years). The countries contributing most reports were the USA (n = 54, 59.3%) and Switzerland (n = 16, 17.6%). ADRs reported most often affected the nervous system and the cardiac function, especially with large tizanidine doses or drugs with CNS and cardiovascular depressant effects. In two cases, a fatal outcome was reported.

CONCLUSION

Despite the existing formal contraindication, the concomitant use of tizanidine and ciprofloxacin can be observed in real-world clinical practice. Reactions mainly affected the central nervous and the cardiovascular system resulting in potentially severe adverse effects. The concomitant use of tizanidine and ciprofloxacin should absolutely be avoided.

Bibliometric analysis of adverse drug reactions and pharmacovigilance research activities in Nepal

Background:

Bibliometric analyses have been used previously to study the measures of quality and impact of research performed in several health-related areas such as adverse drug reactions (ADRs) and pharmacovigilance (PV), etc. This method can assess the research performance of publications quantitatively and statistically. There is no evidence of bibilometric studies analyzing ADRs and PV from Nepal. Therefore, the present study aimed to assess scientific output on ADRs and PV-related research activities in Nepal using a bibliometric analysis of publications from 2004 January to December 2018, that is, 15 years.

Methods:

A systematic search was conducted in PubMed, Web of Science, Google Scholar, Scopus and Nepal Journal Online (NepJOL) databases. ‘Adverse Drug Reactions‘ or ‘ADRs‘ or ‘ADR‘ or ‘Adverse drug reaction‘ or ‘AE‘ or ‘Adverse Event‘ or ‘Drug-Induced Reaction‘ or ‘Pharmacovigilance‘ or ‘PV‘ and ‘Nepal‘. The search covered 15 years (January 2004 to December 2018) of study on ADRs and PV in Nepal. Only articles retrieved from databases were included, whereas published/unpublished drug bulletins, pharmacy newsletters and thesis were excluded. The articles thus retrieved were recorded, and thereafter analyzed. Word count code was used for the analysis of keywords used in the retrieved articles.

Results:

A total of 124 articles were retrieved, with the highest rate of publications in 2006 and 2007, with 16 papers each. Among the articles, 10 (8.1%) were published in Kathmandu University Medical Journal (KUMJ). Single papers were published in 38 different journals. Brief reports (1.6%), case reports (31.2%), case series (0.8%), education forums (0.8%), letters to the editor (5.6%), original research articles (41.9%), review articles (9.7%), short communications and short reports (8.1%) on ADRs and PV were recorded. Out of 124 papers, 52 (41.9%) were original research publications. The majority (74.1%) of research was done in the category of ADR incidence, types, prevention, and management, followed by policy and suggestions for strengthening national and regional pharmacovigilance centers of Nepal (14.5%).

Conclusions:

During the study years, there was an increase in scientific publications on drug safety. A total of 124 published articles were found during bibliometric analysis of ADRs and PV research activities in Nepal.