Does illness have a specific time for recovery, and does medicine hasten it?

Allah has made a cure for every illness, and seeking treatment is a means to healing by His permission, not that the means itself has an inherent effect. A servant does not know what Allah has ordained; one may be cured with or without medicine, or their recovery may be delayed due to not seeking treatment. Therefore, a servant should put their trust in Allah, believe that healing is in His hands, ask their Lord, and then seek treatment in response to the advice of the Prophet, peace and blessings be upon him: "Indeed, when Allah, the Mighty and Majestic, created the illness, He also created the cure, so seek treatment," and his saying: "Yes, O servants of Allah, seek treatment, for Allah has not sent down any disease except that He has sent down a cure for it, except for one disease." They asked, "O Messenger of Allah, what is it?" He said, "Old age."