The Latin name for Coltsfoot is Tussilago farfara and comes from the word tuss meaning cough and lago meaning to dispel. Traditionally it has been used for sore throats, dry coughs, and respiratory condition. Usually, it is made into a tea but has in the past been smoked. Cornish tin miners would regularly smoke Coltsfoot to guard against diseases of the lungs, good luck with that chaps. It has been smoked since early times being recommended by Dioscorides, a famous Roman Physician author of De Materia Medica a 5-volume Greek encyclopaedia about herbal medicines. His contemporary Pliny the Elder also had great things to say about smoking Coltsfoot in his opus Naturalis Historia. However, as a tea do not exceed more than 2 cups a day, it is not recommended for children and infants. And it goes without saying do not consume during pregnancy. Also not recommended if you suffer from heart disease, liver disease or high blood pressure.
It goes without saying that if you're pregnant (or are under the doc for anything) caution should be exercised with herbal decoctions.