Drugs used for Osteoporosis Department of pharmacology 2017.10

Contents Osteoporosis Antiresorptive drugs Bone-forming drugs Mineralization drugs

Osteoporosis Osteoporosis is a disease characterized by low bone mass (bone thinning) that leads to fragile bones and an increased risk of fractures of the hip, spine, and wrist. Normal Osteoporosis Severe osteoporosis

Osteoporosis —symptoms Common symptoms : Back pain Stooped posture Fractures

[ Osteoporosis—types Primary osteoporosis Secondary osteoporosis Postmenopausal osteoporosis Primary osteoporosis Senile osteoporosis Secondary osteoporosis Idiopathic osteoporosis

Osteoporosis—risk factors Factors you cannot change Gender Age; Body size ;Ethnicity; Family history Factors you can change Sex hormones ; Anorexia nervosa; Calcium and vitamin D intake; Medication use; Lifestyle; Cigarette smoking; Alcohol intake

Osteoporosis—diagnosis The Bone Mineral Density Test (BDT) Detect low bone density before a fracture occurs Confirm an osteoporosis diagnosis if you already have one or more fractures Predict your chances of having fractures in the future Determine your rate of bone loss and monitor the effects of treatment

Osteoporosis—diagnosis Bone Mass Density The National Osteoporosis Foundation Recommends a BDT if: You use medications that cause osteoporosis You have type I diabetes ,liver disease, kidney disease or a family history You experience early menopause You are postmenopause over 50 and have at least one risk factor You are postmenopause over 65 and never had a test

Osteoporosis—treatment Comprehensive treatment for osteoporosis deals with:   Proper nutrition Exercise Safety issues to prevent falls Medications

Osteoporosis—medications Antiresorptive drugs: Bisphosphonates, calcitonin, estrogen Bone-forming drugs: Parathyroid hormone, androgen Mineralization drugs: Calcium and vitamin D

Antiresorptive drugs Bisphosphonates(双磷酸盐）—Pharmacological Slow bone loss Increase bone density Reduce the risk fractures

Bisphosphonate—clinical application Osteoporosis in men and postmenopausal women Preventing and treating osteoporosis due to glucocorticoid steroid medications Treating high blood calcium levels due to cancer  Treating multiple myeloma or solid tumor cancers that have spread to the bone

Bisphosphonate—side effects Nausea ,abdominal pain and indigestion  Rash and itchy skin  A temporary increase in parathyroid hormone and serum transaminase（血转氨酶）

Calcitonin Calcitonin analogues (which are manufactured versions of calcitonin) can be useful for treating osteoporosis by slowing the breakdown of bone. Calcitonin is a delicate molecule that would be destroyed by the digestive tract, it must be taken by nasal spray or by injection With side effects of nausea , vomiting and allergic rash et al.

Estrogen Therapy—application Estrogen therapy (ET) reduce bone loss, increase bone density in both the spine and hip, and reduce the risk of hip and spine fractures in postmenopausal women. ET is approved for preventing postmenopausal osteoporosis and are most commonly administered in the form of a tablet or skin patch（经皮吸收）.  

Estrogen Therapy—side effects Taking estrogen alone increases a woman's risk of developing cancer of the uterine lining (endometrial cancer). To reduce this risk, women who still have a uterus (who have not had a hysterectomy（子宫切除）) should usually take a progestin in combination with estrogen

Selective Estrogen Receptor Modulators Selective estrogen receptor modulators (SERMS) are drugs that act like estrogen at some receptors It acts like estrogen for preventing bone loss and improving cholesterol. Currently, only raloxifene （雷洛昔芬）that is approved to prevent and treat osteoporosis .

Bone-forming drugs Parathyroid hormone(PTH)—mechanism With both catabolic and anabolic actions Low dose: PTH stimulate bone turnover and is associated with bone formation（成骨作用） High dose: PTH increase the rate of bone resorption followed by slower rate of bone formation（破骨作用）

Parathyroid hormone(PTH) —application Osteoporosis Primary parathyroid function decline (Intake  vitamins D and calcium together) Generally applies only to first aid

Androgen and anabolic hormone —mechaism Androgen can promote the synthesis of protein and collagen, stimulate bone formation and retention of calcium, phosphorus, and potassium.

Androgen and anabolic hormone —application male osteoporosis Side effect is bigger, the dose of treatment and the pros and cons of relationship is still in the further research

Mineralization drugs Calcium Adding bone mineral and promoting bone mineralization vitamin D3 Increase the absorption of dietary calcium and phosphorus, maintain the balance of calcium and phosphorus and increase the activity of osteoblasts

Calcium—application Acute or chronic hypocalcemia; Tetany disease（手足抽搐）Rickets（佝偻病）; Osteomalacia（软骨病）, osteoporosis, parathyroid function impairment Magnesium poisoning counterpoison（镁中毒解救） (One key piece of advice is to take your calcium in several small doses throughout the day) .

vitamin D3—application Osteoporosis Chronic renal failure For treatment and prevention of vitamin D deficiency Psoriasis （银屑癣）

Key Concepts Osteoporosis is a disease of bone that commonly occurs in elderly people, and is characterized by the degeneration of bone superstructure, a decrease of bone strength , an increase of bone fragility and thus an increased risk of fracture. Drugs available for the prevention and treatment of osteoporosis are catalogued into three types in terms of their actions on affecting calcification and boneover.

Key Concepts Antiresorptive agents, including bisphosphonates, calcitonin, estrogen and iprioavone which decrease the rate of bone loses through inhibiting the activity osteoclasts（破骨细胞）. The second group agents including parathyroid hormone and androgens that promote bone formation by stimulating the activity of osteoblasts（成骨细胞） . .

Review questions Please describe the classification and characteristic of osteoporosis drugs?