Answer to Question 1
Correct Answer: 4
Rationale 1: Drugs given by the buccal, sublingual, or rectal routes bypass the first-pass effect of the liver.
Rationale 2: Drugs given by the buccal, sublingual, or rectal routes bypass the first-pass effect of the liver because the venous supply of the head and lower rectum is not part of the hepatic portal system.
Rationale 3: Drugs given by the buccal, sublingual, or rectal routes bypass the first-pass effect of the liver.
Rationale 4: Drugs given by the buccal, sublingual, or rectal routes bypass the first-pass effect of the liver because the venous supply of the head and lower rectum is not part of the hepatic portal system.
Global Rationale: The venous systems serving the head and the lower rectum are not parts of the hepatic portal system. Thus, drugs that are given by the buccal, sublingual, or rectal routes bypass the first-pass effect of the liver.
Answer to Question 2
Correct Answer: 1
Rationale 1: In order for medication to be available, it must first pass through the liver, where it is broken down into active and inactive molecules. Medications given by the oral route are subject to this first-pass effect; thus, oral doses must be larger than parenteral doses of the same medication.
Rationale 2: Oral and rectal dosages are typically the same.
Rationale 3: The oral dose would not typically be smaller than the intravenous dose.
Rationale 4: The oral and intravenous doses are not typically the same.
Global Rationale: In order for medication to be available, it must first pass through the liver, where it is broken down into active and inactive molecules. Medications given by the oral route are subject to this first-pass effect; thus, oral doses must be larger than parenteral doses of the same medication. Rectal medications doses are similarly affected, so doses would be the same. The oral dose would not typically be smaller than the intravenous dose. Although a drug will still eventually reach the liver by the IV route, it will have an opportunity to also reach its target tissue.