R’ Sherira Gaon (Otzair HaGaonim—Gittin 68b page 152): Our Sages were not doctors and what they said is merely a reflection of what was known by the medical experts of their times and therefore there is no mitzva to accept their statements concerning medicine….
R’ Avraham ben HaRambam (Discourse on Agada): We are not obligated to accept the views of the sages of the Talmud on matters concerning medicine, natural science or astronomy — simply because of their greatness and authority — as we are concerning their explanations of the Torah. That is because concerning Torah, they were the ultimate experts and they had the exclusive authority to teach it as it says in the Torah, “You should do according to the Torah that they teach.”
Ramchal (Introduction to Agada): It is important to know that when our Sages expressed important issues in terms of nature and astronomy — they utilized the science of their days as a metaphor or analogy. Thus, the validity of their ideas is not dependent upon the validity of their descriptions which served only as vehicle to express the ideas. In fact had they expressed their ideas in the more accurate science of today they would not have been understood. It is also important to understand that they believed that material things are influenced and directed by spiritual forces such as angels and demons. The physical world is thus influenced by the higher spiritual worlds and the converse is also true — that the physical world impacts the spiritual world. Whoever isn’t aware of this cannot comprehend our sages at all.
R’ S. R. Hirsch (Letter on Agada p 9–10): in my humble opinion the first principle for understanding the words of our Sages is that they were experts in the law of Gd. They received, transmitted and taught His Torah, commandments, laws and statutes but they were not necessarily experts in science, mathematics, astronomy or medicine — except when it was relevant to knowing and observing the commandments of the Torah. We do not find that secular knowledge was transmitted at Mt. Sinai… The greatest of our Sages knew the wisdom and the science according to what was accepted as true by the leading secular scientists of their day. Thus, they were the equals of these scholars but they did not transcend the secular knowledge of their day.