Clinical PK of opioids

Question 1

What pharmacological effect do opioids have on the CNS?

Answer 1

Analgesia
Sedation
Euphoria
Hallucinations
Tolerance
Dependence

Question 2

What pharmacological effect do opioids have on the CVS?

Answer 2

Bradycardia

Peripheral vasodilation

Question 3

What pharmacological effect do opioids have on the Respiratory System?

Answer 3

Respiratory depression

Cough suppression

Question 4

What other pharmacological effect do opioids have?

Answer 4

GI - (constipation & nausea)
Skin - Itching
Eyes (pin-point pupils) - Miosis

Question 5

Where do opioids undergo first pass metabolism?

Answer 5

Gut wall & Liver

Thus results in low bioavailability

Normal dose - clearance follows first order kinetics - but not in OD

Question 6

Where does clearance take place?

Answer 6

Takes place in kidneys

Clearance is generally high

Question 7

What is Cirrhosis and how does it affect the PK of the drug?

Answer 7

Chronic liver disease

Blood flow obstructed

Blood is diverted around liver into systemic circulation - decreases exposure of drug to liver enzymes

• Decreases metabolism of drugs - thus increases bioavailability
• thus increased plasma conc of drug