Method and devices are provided for extended and controlled delivery of parathyroid hormone to a patient. The method includes implanting a medical device into the patient, the medical device comprising a substrate, a plurality of reservoirs in the substrate, a release system contained in each of the reservoirs, wherein the release system comprises parathyroid hormone; and controllably releasing a pharmaceutically effective amount of the parathyroid hormone from the reservoirs. The parathyroid hormone can be released intermittently, such as once daily over an extended period (e.g., two months, ten months, or more.). The device can further include reservoirs containing a bone resorption inhibitor or other drug for release. The devices are useful in delivering PTH for the treatment and prevention of bone loss, such as associated with osteoporosis.