BACKGROUND: Herbal medicine (HM) regulation is less developed than that of allopathic medicines, with some countries lacking specific regulations. OBJECTIVE: For the purpose of informing a registration system for HMs in Kuwait, which does not manufacture but imports all HMs, this study compared the similarities and differences between the current HM registration systems of five countries. METHODS: The five countries were selected as major source countries of HM in Kuwait (United Kingdom (UK), Germany and United States of America (USA)) or because of geographical proximity or size and approach (United Arab Emirates (UAE) and Kingdom of Bahrain). Documentary analysis of HM classification systems was performed by reviewing the regulatory and law documentation of these countries' drug regulatory authority websites. Data on HM definition, classification and the main requirements for registration were extracted and analysed for similarities and differences. RESULTS: There was diversity in the classification of HMs across all five countries including terms used, definitions, type of law, requirements, restrictions and preparation type. The regulatory authorities of the UK, Germany, UAE  and Kingdom of Bahrain offer simplified registration for HMs, where plausible efficacy as a result of established traditional use is sufficient. In USA, the concept of traditional use does not exist, instead, the product can be categorised as a dietary supplement where no assessment or evaluation is required prior to marketing. CONCLUSIONS: Owing to the inconsistencies in how drug regulatory authorities define HMs, it will be important to design a clear definition of what constitutes a HM in Kuwait, which is a country that does not produce and register its own products but assesses products registered elsewhere.