At on time, the late 1960s-late 1970s when many US students were studying medicine abroad, some attended French medical schools. If admitted, they usually started with the second year on the basis of having a US college degree. The language of instruction was and is in French, France being about the last country in the world you would expect any school to teach in English. [At one time French was THE international language; English supplanted French as the international language after WWII. The loss of two wars, especially the second when France was occupied by the Germans, two English speaking armies were primarily responsible for ending the occupation and restoring the Republic, and the loss of their overseas colonies (especially Viet Nam when the US refused military help), engendered an almost xenophobic reaction. French pride in their history, culture and language suffered a blow. To make a long story short, the use of French became almost a mandate. Franglais was deplored].
Medical students were (I am not sure if they still are) generally admitted under what we would call an "open admissions policy." Lecture classes were overcrowded. Then came the crunch: limited space was available for the clinical curriculum, a bottleneck was created, about the equivalent of the US bottle neck between our undergraduate curriculum and entry into the first year of medical school. This is known as "numerus clausus" (found also in some other European countries). Thus, there is no guarantee that once admitted to a French medical school a student would have a high probability (as there is in the US) of earning the medical degree.
Belgium was more receptive to US students and many went, primarily to French speaking Louvain, to earn the medical degree. Italy Spain and Mexico were also common destinations. The exodus to Europe tailed off drastically when the English speaking Caribbean medical schools opened up to cater primarily to Americans, St. George's on Grenada being the pioneer. Now, there are a few other legitmate medical schools in eastern Europe advertising for American students and offering instruction in English, but none that I am aware of in France, Belgium, Italy, Spain, the Netherlands, Germany, Sweden, Norway, Denamark. In Dublin, two medical schools take a few Americans each year. There are a few Americans studying in Britain; there are special regulations for applying; contact a British consulate.
If you are interested in studying medicine in France contact the Cultural Section of a French consulate for information.