Doppelherz is German for "Double Heart".

It is also the brand name for a line of food supplements that are supposed to be good for your cardiovascular system with ingredients like lecithin, garlic, ginseng and diverse vitamins. They are not classified as "real" drugs, meaning they can be sold at any store, not only in a pharmacy with a prescription from a doctor.

The original "Doppelherz Energie Tonikum" was invented in 1919 (claims the website) - the manufacturer is the Queisser Pharma GmbH based in Flensburg. The Doppelherz logo is quite well known (at least in Germany, that is) - take a look at