Pharmacotherapy
Calcium and vitamin D supplementation
1、Calcium supplements
The recommended daily intake of 800mg (elemental calcium amount) for adults is the appropriate dose for maintaining bone health, if the calcium supply in the diet is insufficient, calcium supplements can be used.
2、Vitamin D
The recommended daily intake for adults is 800IU, but vitamin D deficiency is common in the elderly due to intake and absorption problems, reduced outdoor activities, insufficient sunlight and reduced ability of skin to synthesize vitamin D3 (about 40% of adults). The recommended dose of vitamin D for the elderly is 800 to 1200 IU/d. Oral supplementation with natural vitamin D is the safest. When there is renal hypofunction, its ability to convert 25-OH-VD3 to 1,25-(OH)2 – VD3 is reduced. Alfacalcidol or osteotriol are appropriate.
Drug selection for different types of OP
1、Age-related osteoporosis
Calcium preparations + vitamin D + bone resorption inhibitor (alendronate)
2、Postmenopausal osteoporosis
(1) Hormone replacement therapy (HRT) Combining estrogen or selective estrogen receptor modulators with the basic treatment, i.e. calcium + VD, is an effective measure to prevent and treat postmenopausal OP in women.
①Indications: Women with menopausal symptoms and/or osteoporosis and/or risk factors for osteoporosis are advocated to start early menopause with a greater benefit/risk ratio.
(2) Contraindications: Estrogen-dependent tumors (breast cancer, endometrial cancer), blood test disorders, unexplained vaginal bleeding and active liver disease and connective tissue disease are absolute contraindications.
(2) Selective estrogen-regulating factor drugs: can effectively inhibit osteoclast activity and reduce bone conversion to premenopausal levels in women.
(3) Calcitonin: It can inhibit the biological activity of osteoclasts and reduce the number of osteoclasts, and its prominent feature is that it can significantly relieve bone pain, which is effective for chronic pain caused by fragility fracture or skeletal deformation and bone pain caused by bone tumor and other diseases.
(4) Bisphosphonates: can effectively inhibit osteoclast activity and reduce bone conversion, which is beneficial to postmenopausal women with severe osteoporosis and can reduce the incidence of vertebral fractures and hip fractures.
(5) parathyroid hormone (teriparatide): it has the effect of promoting bone formation, and its intermittent use can effectively treat severe postmenopausal osteoporosis, increase bone density and reduce the risk of vertebral and non-vertebral fractures, and is suitable for patients with severe osteoporosis.
Secondary osteoporosis
(1) High urinary calcium secondary to hyperparathyroidism: hydrochlorothiazide 12.5-25mg/d can be applied to reduce urinary calcium loss; in addition, bisphosphonates or calcitonin can be chosen.
(2) OP due to glucocorticoids: glucocorticoids stimulate bone resorption by osteoclasts and inhibit bone formation by osteoblasts. Treatment can be applied to bisphosphonates, calcium and vitamin D supplementation.
Precautions for drug use Estrogen
- Strictly grasp the indications, strictly control the contraindications of estrogen, and regularly monitor plasma estrogen levels. Long-term drug maintenance therapy is required, and relapse is likely if the drug is discontinued immediately after symptom relief. It is recommended to start the application during perimenopause.
The preventive or therapeutic effect of combining estrogen with calcium, vitamin D, progestin and androgens is better than that of single medication, and the dosage of estrogen can be reduced.
- Monitor estrogen adverse reactions and regularly check pelvis, breast, blood lipids, bone density and other indicators.
Calcitonin
1、People who are allergic to proteins may be allergic to calcitonin, so skin sensitivity test should be done before use, and it should be used with caution for people with skin rash and airway asthma.
- Secondary hypoparathyroidism may occur in a few patients during high-dose short-term treatment. Use with caution in women during pregnancy.
Bisphosphonates
1, in order to reduce adverse reactions, do not use 2 bisphosphonates at the same time.
2, esophagitis is the main adverse reactions, fecal occult blood positive, with esophageal hiatal hernia, peptic ulcer should not be applied. In order to avoid adverse reactions in the digestive tract can also be administered intravenously.
3, hypocalcemia is prohibited; cardiovascular disease, children, pregnant and lactating women, drivers caution; hypersensitivity to bisphosphonates is prohibited.
4, multivalent cations can make the absorption of bisphosphonates decreased, the use of the process should be monitored plasma calcium, phosphorus and platelet count.
5, severe renal insufficiency (Ccr <35ml/min) is prohibited. When high concentration is injected rapidly, it may chelate with calcium in the blood to form complexes leading to renal failure. Slow injection for 2~4h can effectively avoid the above adverse reactions.
- Not to be used in combination with NSAIDs. Combining with antacids, iron or drugs containing 2-valent metal ions will reduce the bioavailability of this product. It is recommended to take antacids, calcium, etc. only lh after taking diphosphonates.
7、A few years of medication may cause bone, joint or muscle pain, osteonecrosis of the jaw, occipital osteitis, etc., which should be paid attention to.
8, oral bisphosphonates should be given in the morning on an empty stomach to avoid irritation of the esophagus and stomach. It is recommended to take it with sufficient amount of water, keep sitting or standing position, should not eat or lie down within 30 minutes after taking it, should not drink milk, coffee, tea, mineral water, juice and calcium-containing drinks. If sore throat, painful swallowing and chest pain occur during pharmacotherapy, prompt treatment should be given.
Vitamin D and its derivatives
1、Prevent hypercalcemia and hypercalcemia, monitor blood calcium level and urinary calcium excretion regularly.
2, large amounts of continuous application of vitamin D can occur poisoning, the recommended dose of vitamin D is 800 to 1200 IU, which is far from the poisoning dose. Generally adults over 50,000IU/d, children over 20,000IU/d, for several months may occur poisoning.
- Contraindicated in combination, active vitamin D metabolites and thiazide diuretics have the risk of hypercalcemia. Glucocorticoids have an antagonistic effect on vitamin D, which can reduce the absorption of calcium and phosphorus in the digestive tract and lower the blood calcium concentration, and the urinary calcium level must be measured regularly. Estrogen can increase calcium absorption, should reduce the amount of active vitamin D accordingly; alfacalcidol and magnesium-containing preparations used together can cause hypermagnesemia, should be used with caution. Kolalenamide, mineral oil, aluminum thioglycollate, etc. can reduce the absorption of vitamin D in the small intestine. Digitalis and vitamin D should be used with caution, because vitamin D can cause hypercalcemia, easily induced arrhythmia.
4, with hypercalcemia, hyperphosphatemia and hyperlipidemia, arteriosclerosis and cardiac insufficiency; hyperphosphatemia with renal rickets is prohibited; excessive use during pregnancy can lead to fetal malformation, parathyroid suppression and long-term hypocalcemic convulsions in newborns, should be used with caution.
5, calcitonin and vitamin D together can offset the former’s efficacy on hypercalcemia.
