Medical SEO is so general that it is hard to put a finite timeline on when it will “work.” The answer depends on your goals and what you are starting with. A new practice website with little content and no authority will usually take longer than an established site that already has pages ranking and steady impressions in search.
With that said, most of the tactics that drive medical SEO are the same tactics that drive SEO in every other industry. You still need to understand what queries you already appear for in Google Search Console, spot patterns, and build a strategy around what is already working. From there, you uncover new opportunities, build topical authority with high quality content, improve on page experience and internal linking, and earn relevant backlinks that reinforce credibility.
The main difference is that medical content often falls under YMYL considerations, meaning trust and accuracy matter more. Medical SEO still runs on the same pillars, but it requires a higher standard of quality, clarity, and legitimacy to compete consistently.