28. Oral Drug Delivery

Question 1

What are symptoms of excessive caffeine intake?

Answer 1

Rapid or fluttering heartbeat, light-headiness, upset stomach & overall feeling of jitteriness

Question 2

What is the problem in delivering poorly soluble drugs orally?

Answer 2

Dissolving

Question 3

What are the four main reasons for oral routes of administration?

Answer 3

• Reason 1: Systemic delivery of drug for many non-GI specific conditions
• Reason 2: Treating GI conditions:
  1. Gastro-oesophageal reflux disease (GORD)
  2. Duodenal and stomach ulcer disease (PUD)
  3. Gastritis
  4. Non-ulcer dyspepsia (NUD)
  5. Oesophageal & gastric cancer
  6. Inflammatory Bowel Diseases
  7. Colon cancer and many more…
  
  • Reason 3: Unused medications cost the NHS around £300 million every year
  • Reason 4: The more acceptable and familiar form

Question 4

What is involved in oral absorption

Answer 4

Systemic activity of an API molecule after oral administration it must be absorbed from the intestine to the bloodstream/site of action

Question 5

What is the most dominant mechanism of drug absorption from the intestinal lumen (GIT)?

Answer 5

Passive diffusion

Question 6

What are the three pathways by which drug molecules cross the intestinal epithelium?

Answer 6

1. Transcellular Pathway → Passive diffusion across the cell membrane
2. Paracellular Pathway → Passive diffusion between adjacent cells
3. Carrier-Mediated Pathway → Carrier mediated transport

Question 7

How do Lipophilic molecules cross the membrane?

Answer 7

Transcellular diffusion