Shailah of the Week by Rabbi Zvi Nussbaum
Rabbinic Coordinator, Kosher Hotline Administrator for the Orthodox Union
Many people are symptomatic these days with diseases ranging from the common cold to Coronavirus. People with coughs and running noses will be looking for medications to help relieve some of the symptoms. As we search for over-the-counter drugs for relief, we are certainly concerned about the kashrut.
Liquid medicines can have a substantial amount of glycerin, often about 10%. Glycerin can be made from vegetable oil or from animal fat (or it can be synthetic). If one is concerned about the source of the glycerin, one should dilute the liquid medicine at a ratio of 1 part medicine to 6–8 parts water or juice. Thus, the glycerin will be less than 1 part in sixty and will be nullified.
This is a major concern in these times, but the glycerin ratio and its source are the key determinant factor.