Calcium carbonate tablets (Caltan) are mainly used for the prevention and treatment of calcium deficiency, and their indications and medication precautions should be comprehensively considered in conjunction with the patient's physiological and pathological conditions. The following provides a detailed explanation from three aspects: indications, contraindications, and special precautions.

1 Indications

(1) Osteoporosis prevention and treatment, as a basic calcium supplement, should be combined with vitamin D3. The recommended daily dose for postmenopausal women is 1000-1200mg. (2) During the acute symptom period of hypocalcemia correction, it can be used for a short period of time up to 2000mg/day, and blood calcium concentration should be monitored every 8 hours. (3) It is recommended to start supplementing calcium during pregnancy to prevent preeclampsia from 20 weeks of gestation, but it is necessary to control blood calcium levels to ≤ 2.6mmol/L.

2 Contraindications

(4) Diseases related to hypercalcemia, including hyperparathyroidism and malignant tumor bone metastasis, are absolutely contraindicated. (5) Patients with severe renal insufficiency and GFR<30ml/min should not use it, as it may accelerate the process of vascular calcification. (6) Patients with calcium sensitive arrhythmias such as QT interval prolongation syndrome should avoid using it.

3 Medication precautions

(7) It is recommended to take the medication with meals in divided doses to reduce gastrointestinal irritation and increase absorption rate by about 20%. (8) Drug interactions with quinolone antibiotics should be taken 2 hours apart, and thyroid hormone preparations should be taken 4 hours apart. (9) Long term monitoring: Check the urinary calcium/creatinine ratio every 3 months. If it exceeds 0.3mmol/mmol, reduce the dosage.

4 Adjustments for Special Groups

(10) Elderly people are advised to use bisphosphonates in combination, as calcium supplementation alone cannot effectively reduce the risk of fractures. (11) Liquid dosage forms are recommended for children under 6 years old to avoid the risk of accidental ingestion of tablets. (12) Dialysis patients should receive medication after dialysis to prevent the calcium phosphorus product from exceeding 4.4 mmol ²/L ².