Pharm from passing FRACP

Question 1

What is the difference between a generic and biosimilar drug?

Answer 1

• genetics are small molecule copies of small molecule innovators with exact physio-chemical replicas of the originator drug
• biosimilars are LARGE and complex molecules; cant be like generics as may arise from different clone lines*

Question 2

Bisphosphonates are like pyrophosphates. What implications does this have with the bones?

Answer 2

• high affinity for bone - likely to remain in the bone for years!
  *low risk of low energy femoral fractures + ONJ if prolonged use
  –> consider a drug holiday - fiver years for aldo/ris & 3 years for zol

Question 3

What are the adverse effects of bisphosphonates?

Answer 3

• poor intestinal absorption (not given with meals/dairy products)
• hypocalcaemia
• oesophagitis, oesophageal erosions, ulcers
• renal impairement
  *low risk of low energy femoral fractures + ONJ if prolonged use

Question 4

What is the risk of stopping denosuab?

Answer 4

• a reminder mechanism if inhibiting formation + action of osteoclasts
• when ceased, bone turnover markers increase + BMD decrease
• vertebral fractures may occur soon after
  *no firm guidelines on what to do after stopping denosumab

Question 5

Explain the role of inducers vs inhibitors in the CYP system

Answer 5

• inducers - the CYP system is particularly suseptible; this means the substrates for this CYP are kicked off
  Carbemazepine, phenytoin, dex - inducers
  they may kick off poor hydrocortisone

Question 6

Hydrocortisone is metabolised by CYP3A4. Ketoconazole inhibits CYP3A4. How does this affect the dose of hydrocortisone?

Answer 6

increases it

Question 7

What is the formula used to screen and monitor patients with CKD?

Answer 7

CKD-EPI

Question 8

What is the formula used to calculate the renally adjusted dose of medications?

Answer 8

Cockcroft-Gault formula