Customize your care with Boiron single medicines for highly targeted relief. Rumex Crispus 1M is a homeopathic dilution of Rumex Crispus that relieves Dry Cough Worsened By Breathing Cold Air. The pellets melt in your mouth and can be taken on the go, no food or water needed. (BoironUSA.com) About Boiron: With more than 85 years of expertise, Boiron is a trusted brand that prides itself on quality manufacturing and responsible environmental practices. All products are made according to the highest standards of cGMP and formulated with HPUS ingredients for purity.