Ca & Bone Pharmacology Flashcards
Hypercalcemia
Frequency
2 Usual causes
Common
90% due to malignancy or hyperpaathyrodism
3 principals for hypercalcemia therapy
- Increase urinary calcium excretion
- Diminish intestinal absorption of calcium
- Inhibit accelerated bone resorption
Which medications should be avoided when treating hypercalcemia?
Thiazides
Vitamin D
2 dietary changes to treat hypercalcemia
Curtail dietary intake Ca++ and Vitamin D
Increase Na and H2O intake
First line therapy for hyercalcemia
Bisphosphonates
Bisphosphonates
Name one Indications Mechanism Side effects Duration of actins
Name one
- Zoledronate (Injection, yealy)
- Ibandronate (injects every 3 months)
- Alendronate/fosamax (Oral)
Indications
- Oseoporosis
- Hypercalcemia
Mechanism
- Nonhydrolyzable analogues of pyrophosphate
- Incorporated into bone
- Osteoclasts then ingest the drug
- Apoptosis triggered in osteoclasts
Side effects
- Hypocalcemia
- GI upset
- Acute phase reaction: Transient flu-like syndrome
- Nephrotoxicity
- Jaw necrosis (cancer patients & sometimes occurs if patient is on medication and has dental procedures)
Dosing
- IV administration
- Prolonged effect for weeks to months
Duration of action
Second line treatment for hypercalcemia
Calcitonin
Calcitonin
Indications Which cell normally produces calitonin? Potency of synthetic calcitonin? Mechanism? Duration Dosing?
Indications
- HyperCa
- Pain relief for bone cancer
Normally produced by
- C cells of thyroid
Potency
- synthetic salmon calcitonin – 50X more potent, by SC or IM injection
Mechanism
- cell surface G-protein-coupled receptor on osteoclasts ↓ bone resorption
- ↑ urinary calcium excretion
Duration
- Safe & rapid but short
- Used in severe cases along with other (slower acting) therapies
Dosing
- Nasal spray
Hypocalcemia
Frequency
Causes (5)
Frequency
- Less frequent than hypercalcemia
Causes
- Chronic & acute renal failure
- Vitamin D
- Mg Deficiency
- Acute pancreatitis
- Hypoparathyrodism
What must be measured to determine whether a patient has hypocalcemia?
Ionized Ca
Two types of oral Ca supplements?
How do you decide which to use
Name the bio available form
Which form has highest Ca content
All Ca supplements require
Three side effects of all Ca supplements?
Ca carbonate
mild & asymptomatic hypocalcemia (8.0- 8.5 mg/dL)
IV Calcium
for acute or symptomatic (
Ca carbonate
Indication
Mechanism
Must be given with X or else give Y if patient has Z
Ca carbonate
Indication
mild & asymptomatic hypocalcemia (8.0- 8.5 mg/dL)
Mechanism
- Want to incease intestinal Ca
X: Vitamin D
Y: Calcitriol (1,25 vitamin D)
Z: Hypoparathyrodism
IV Ca
Indication
Mechanism
Why is Ca gluconate better than Ca chloride
Indication
for acute or symptomatic (<7.0 mg/dL and clinical evidence of functional hypocalcemia)
Mechanism
- Directly increases serum Ca
Why Ca gluconate better than Ca chloride?
- calcium chloride (more Ca+, more rapid but more irritating to veins)
Hyperparathyrodism
Frequency
Causes (3) which is appropriate
Excess PTH caues
Frequency
- Common
Causes
Primary: parathyroid adenoma or hyperplasia, carcinoma (rare) – treat with parathyroidectomy
Secondary (appropriate response to low vitamin D and Ca): chronic renal failure, malabsorption syndromes
Tertiary – progression into autonomous hypersecretion of PTH associated with hypercalcemia
Excess tries to raise PTH levels
Only treatment of parathyroidism
Calcimimetics
Cinacalcet Hydrochloride
Indications
Mechanism
SE
Indications
- secondary hyperparathyroidism in chronic kidney disease
- hypercalcemia in parathyroid carcinoma
- primary HPT
Mechanism
- Activates CaSR which fulls parathyroids to believe Ca levels are high so that they stop producing PTH
SE
- hypocalcemia, nausea, vomiting
Random facts - just read
> 20 million in USA
4:1 female:male
Spine, hip, wrist fractures
50% postmenopausal women will fracture in lifetime
20% one year mortality after hip fracture
$17 billion annually (2005
Three mechanisms for prevention
Optimize calcium and vitamin D intakes throughout life
Weight bearing exercise
Fall Prevention
Vitamin D
Mechanism
Deficency causes Name 1. vitamin D2 2. cholecalciferal 3. 1,25(OH)2D
SE
What can hamper absorption of vitamin D?
Mechanism
↑ GI absorption of calcium
Deficiency causes
- secondary hyperparathyroidism
SE
- toxicity (hypervitaminosis D)
Hamper absorption
- Fat malabsortion
Name 5 big catagories for the treatment of osteoporosis
- Bisphophonates
- Synthetic estrogens (SERMS)
- Danosumab
- Calcitonin
- Intermittent high dose PTH
1st choice treatment for osteoporosis?
Bisphosphnates
Estrogen
Why are synthtic agents used
Synthetic agents have no effect on?
Use synthetics because
- May ↑ risk of heart attacks, strokes, breast cancer, migraines, blood clots (WHI study)
Synthetics have no effect on menapausal symptoms
Raloxifene
Class
Mechanism
Advantages even though not that effective
Class
selective estrogen receptor modulator
Mechanism Agonist (estrogenic) effects in bone, antagonist in breast and uterus
Advantages
- Oral medication
What is the difference in action when PTH levels kept high continously versus intermittent elevation?
Continuous elevations > 2hrs/day - ↓ bone mass
Intermittent elevations ≤ 1 hr/day - ↑ bone mass
Teriparatide
Class Mechanism Dosing SE Which populations Use with bisphosphonates
Class
- Recombinant 1-34 aa PTH
Mechanism
- Stimulates osteoblasts and new bone growth, ↑ turnover, improves micro-architecture
Dosing
- Daily subcutaneous injection (intermittent), short half life, expensive, use x 24 months, severe osteoporosis
SE
- HyperCa
- Hypercalciuria
Population
- High risk fracture
Use with bisphosphonates
- Controversial
