From Kollel Eretz Hemdah, Ask the Rabbi (link):
QUESTION: I heard that there is a written manual in the Jewish holy books which lists remedies to various illnesses; an ancient guide to remedies; my husband is currently on the waiting list for a liver transplant; pursuing a transfusion he contracted years ago hepatitis C(emphasis added)
ANSWER: There are some medical remedies mentioned in the Talmud, as well as other, later works (such as the Rambam’s book on medicine - he was also a doctor). However, these are not special, secret remedies. The Torah tells us “v’rapoh y’rapeh”, “and He shall certainly heal (Shmot 21:19)”. The Talmud learns from here that it is proper and required to seek medical help to deal with illness (Bava Kama 85a).
The remedies mentioned in ancient sources are based on the best medical information available to them at their time. Where modern medicine agrees, wonderful. When not, one should follow present-day experts. I hope and assume that your husband is receiving the best medical attention available to you.
We, of course, do not rely on medical help, alone. We are instructed to turn to Hashem for help, for He is the true Healer. However, we do this with different types of remedies. We rededicate ourselves to the proper service of Hashem, which is our purpose for being put in this world. We have a blessing in each Shmoneh Esrei prayer for health, in general. It is appropriate to insert there our requests regarding any specific people who need a refuah. We can say Tehillim on behalf of the ill. We can go to holy places to pray and ask holy people to join us in prayer.
Will all of these things heal? Maybe yes, maybe no. But the good deeds will all be remembered above and will manifest themselves in ways we may never know. The ancient “remedies” of prayers and good deeds, along with best in modern medicine, are the best we can do.
Our best wishes for your husband’s full and speedy recovery. If you would like to send us his name (Jewish name and mother's Jewish name), we will, G-d willing, include him in the list of the ill for whom we pray.