The document discusses clinical pharmacology and provides information on pharmacokinetics and pharmacodynamics. It covers topics such as absorption, distribution, metabolism, and excretion of drugs. It discusses how factors like food, gut motility, and malabsorption can impact drug absorption. It also mentions how drug interactions during absorption can occur through precipitation, chelation, or effects on gut flora. The example given is explaining the full effect of digoxin would not be seen for a week, which relates to the drug's half-life.

1. Clinical Pharmacology
for MRCP 1
Andrew Webb

2. Topics
Clinical Pharmacology:
• The principles behind the prescribing process
Therapeutics:
• The process of Medical treatment

3. Main Topic
Pharmacokinetics
&
Pharmacodynamics
Interaction
Adverse effects and
toxicology
Specific situation/
susceptibility
• Individual drugs: classic & new
• Basic science & Mechanisms of action
• Clinical trails

4. Pharmacokinetics
“What the body does to drugs”
• Absorption
• Distribution
• Metabolism
• Excretion

5. PK: Absorption
• GI motility:
– Migraine s absn of paracetamol
• Malabsorbtive states:
– Coeliac s absn digoxin
• But absn propranolol
• Food: milk chelates tetracycline

6. Interactions!
Precipitant Object

7. May be two-way
Precipitant Object

8. PK interaction: absorption
• GI motility
– Opioids/antimuscarinic TCADs
– Metoclopromide
• Absn
– Cholestyramine – digoxin, warfarin (anionic)
• Chelation
– By antacids (Al, Mg, Ca) of pred, iron + tetracylines,
• Gut flora –
– Antibiotic vit. K synthesis potentiate warfarin

9. A 65-year-old was advised to start
oral digoxin at a dose of 205 µg
daily. His physician explained that
the full effect of this treatment
would not be apparent for at least
a week.

10. Which one of the following
pharmacokinetic variables did the
physician use to give this
explanation?

11. Which one of the following pharmacokinetic variables
did the physician use to give this explanation?
• Bioavailability
• Half-life
• Plasma protein binding
• Renal clearance
• Volume of distribution