Pharmacology and Pain Management Flashcards

Which local anesthetic is unique in that it is the only amide with an ester side chain, allowing partial metabolism in the plasma by pseudocholinesterases?

Answer: Articaine

Articaine contains a thiophene ring and a supplementary ester linkage, enabling approximately 90% of the drug to be hydrolyzed in plasma, reducing hepatic load.

Methemoglobinemia is a rare but serious adverse effect most associated with which local anesthetic used for topical application?

Answer: Benzocaine

Benzocaine oxidizes hemoglobin to methemoglobin, reducing oxygen-carrying capacity; this is especially dangerous in infants and when applied in large amounts.

Which of the following is a contraindication to epinephrine use as a vasoconstrictor in local anesthesia?

Answer: Uncontrolled hyperthyroidism with tachyarrhythmia

Uncontrolled hyperthyroidism with cardiac arrhythmias is a relative contraindication because epinephrine can trigger or worsen life-threatening tachyarrhythmias.

A patient on long-term corticosteroid therapy may require supplemental corticosteroids before stressful dental procedures due to risk of which condition?

Answer: Addisonian crisis (adrenal insufficiency)

Chronic exogenous steroid use suppresses the HPA axis; the adrenal glands cannot mount a stress response, potentially causing acute adrenal insufficiency (Addisonian crisis).

Which drug used to treat seizure disorders is most commonly associated with drug-influenced gingival enlargement?

Answer: Phenytoin (Dilantin)

Phenytoin causes gingival fibroblast proliferation, resulting in fibrous gingival overgrowth affecting approximately 50% of long-term users.

When performing nitrous oxide/oxygen conscious sedation, what is the recommended minimum oxygen concentration to maintain throughout the procedure?

Answer: 30%

A minimum of 30% oxygen is maintained during nitrous oxide sedation to prevent hypoxia; room air contains 21%, so this exceeds normal atmospheric oxygen levels.