ADVANCED PHARMACOLOGY: NR 566 Week 1 Notes Ch. 21, 33, & 41 Chapter 21: Drugs Affecting the Endocrine System

NR 566 Week 1 Notes Ch. 21, 33, & 41 Chapter 21: Drugs Affecting the Endocrine System Pharmacokinetics  Absorption and Distribution o All oral bisphosphonates potentially cause esophagitis and gastric irritation o Absorption and bioavailability of oral doses are significantly reduced by the presence of food in the gut or other preparations containing divalent cations. o To enhance absorption, the patient takes the drug with 8 oz of water, No other food or drink should be ingested, and the patient must remain upright for at least half an hour (1 hour with ibandronate). o all mainly distributed to bone. o Their terminal half-life in bone is exceedingly long, varying from more than 10 years for alendronate to more than 90 days for etidronate. o The half-life of risedronate is much shorter, at 480 hours; ibandronate is 220 hours; zoledronic acid is 167 hours; and tiludronate is 150 hours these times are thought to represent the dissociation of the drug from the bone surface, rather than its time within the bone. o Most bisphosphonates are Pregnancy Category C. Pamidronate and zoledronic acid are Category D o All bisphosphonates are used with extreme caution during breastfeeding; zoledronic acid binds to bone for long periods so is never used in lactating mothers..............CONTINUED*