Background Deliberation no. 56/CD/2008 from the Portuguese Authority of Medicines and Health Products (INFARMED) approves the regulation of medicinal gases set out by Decree-Law no. 176/2006, which considers them as medicines for human use. This Deliberation addresses the manufacture, packaging, labelling, package leaflet, technical management, transportation, distribution, marketing, supply and home delivery of medicinal gases. In this context pharmacists play a proactive role by providing essential information about the proper use of these medicines.

Purpose To develop a database of medicinal gases that allows hospital pharmacists to detect medicinal gases/other medicinal product interactions and validate medical prescriptions in a quick, safe and effective way.

Materials and Methods Review of the summary of product characteristics (SPC) of all medicinal gases currently available in Portugal and consultation with the manufacturers of medicinal gases and analysis of responses. A literature review was also performed, through research and analysis of articles obtained from PubMed since January/2007 to September/2012, intersecting the terms ‘medicinal gases’ and ‘medical gases’.

Results A total of 6 medicinal gases currently available in Portugal were analysed: medicinal air, nitric oxide, nitrous oxide, nitrous oxide/oxygen, oxygen and xenon. The main interactions of these gases with other medicinal products are: i) nitric oxide: oxygen, almitrine, nitroglycerin, sodium nitroprusside, phenylephrine, phosphodiesterase inhibitors, prilocaine, sulfonamides; ii) nitrous oxide: cyanocobalamin, drugs that depress the central nervous system (CNS), methotrexate; iii) oxygen: antiarrhythmics, bleomycin, chloroquine, chlorpromazine, corticosteroids, dactinomycin, doxorubicin, nitrofurantoin, phytomenadione, sympathomimetics; iv) xenon: antihypertensives, drugs that depress the CNS, other inhaled anaesthetic agents, sympathomimetics. No interactions were found with medicinal air. The database developed also describes the interaction mechanisms for each medicinal gas with each drug mentioned and the measures recommended to prevent major side effects.

Conclusions The database produced is a valuable tool for Portuguese hospital pharmacists who dispense medicinal gases, contributing to validating prescriptions for these medicines quickly and effectively.

No conflict of interest.