DAVIS'S DRUG GUIDE FOR NURSES
19TH EDITION
• AUTHOR(S)APRIL HAZARD
VALLERAND; CYNTHIA SANOSKI
TEST BANK
1
Drug Reference: Warfarin — Vitamin K Antagonist — Drug
Interactions & Detecting and Managing Adverse Drug Reactions
Stem: A 68-year-old with new atrial fibrillation is started on
warfarin 5 mg PO nightly. Current meds: trimethoprim-
sulfamethoxazole (for UTI started 2 days ago). INR today is 1.6
(target 2–3). Which is the most appropriate nursing action now?
A. Give the 5 mg dose and recheck INR in 2 weeks.
B. Hold warfarin today and contact prescriber to consider
lowering dose or monitoring INR closely.
C. Give warfarin and instruct patient to avoid green leafy
vegetables.
,D. Change TMP-SMX to nitrofurantoin without contacting
provider about warfarin.
Correct Answer: B
Rationales
Correct (B): TMP-SMX can potentiate warfarin effect by
inhibiting warfarin metabolism and displacing protein binding,
increasing bleeding risk. Holding the dose and contacting the
prescriber for dose adjustment and more frequent INR checks is
the safest immediate nursing action.
A: Giving the dose without addressing the interacting antibiotic
risks excessive anticoagulation and bleeding.
C: Avoiding leafy greens is general education but irrelevant to
the acute drug–drug interaction and does not address
immediate safety.
D: Changing antibiotics is a prescriber decision; acting without
contacting provider is outside nursing scope and still requires
INR monitoring.
Teaching point: TMP-SMX increases warfarin effect — hold dose
and notify prescriber; monitor INR frequently.
Citation: Vallerand, A. H., & Sanoski, C. (2025). Davis's Drug
Guide for Nurses (19th ed.). [Drug Interactions; Detecting and
Managing Adverse Drug Reactions].
2
,Drug Reference: Gentamicin — Aminoglycoside Antibiotic —
Renal Impairment & The Pediatric Patient
Stem: A 4-year-old with complicated UTI is prescribed
gentamicin IV q8h. Pre-dose trough level is 2.4 µg/mL
(therapeutic trough goal <1 µg/mL), BUN 28 mg/dL, Cr 0.6
mg/dL (baseline 0.3). Temperature 38.5°C. What is the next
nursing action?
A. Administer scheduled dose and repeat trough in 24 hours.
B. Hold dose and notify prescriber to adjust dosing interval and
obtain repeat levels.
C. Give the dose and schedule a nephrotoxic monitoring sheet
for tomorrow.
D. Administer dose and request an audiology consult after
therapy.
Correct Answer: B
Rationales
Correct (B): Elevated trough and rising creatinine indicate
accumulation and nephrotoxicity risk in a child; holding dose
and contacting prescriber for dosing interval adjustment and
repeat levels prevents further toxicity.
A: Administering despite supratherapeutic trough risks
worsening renal injury and ototoxicity.
C: Monitoring later without immediate action fails to address
current supratherapeutic level.
D: Audiology is appropriate for ototoxicity monitoring, but
immediate holding/adjusting dose is higher priority.
, Teaching point: High gentamicin troughs + rising creatinine →
hold, notify prescriber, adjust interval and monitor levels.
Citation: Vallerand, A. H., & Sanoski, C. (2025). Davis's Drug
Guide for Nurses (19th ed.). [Renal Impairment; The Pediatric
Patient].
3
Drug Reference: Methotrexate — Antimetabolite,
Antirheumatic/Antineoplastic — Females of Reproductive
Potential & REMS Overview
Stem: A 29-year-old woman with severe psoriasis is starting
methotrexate weekly. She reports irregular contraception use.
Which nursing action is highest priority before administering
the first dose?
A. Administer and advise contraception starting next menstrual
cycle.
B. Withhold medication and ensure reliable contraception and a
negative pregnancy test.
C. Give medication and schedule monthly pregnancy tests.
D. Advise abstinence but give medication as ordered.
Correct Answer: B
Rationales
Correct (B): Methotrexate is teratogenic; for females of
reproductive potential it is contraindicated without reliable
19TH EDITION
• AUTHOR(S)APRIL HAZARD
VALLERAND; CYNTHIA SANOSKI
TEST BANK
1
Drug Reference: Warfarin — Vitamin K Antagonist — Drug
Interactions & Detecting and Managing Adverse Drug Reactions
Stem: A 68-year-old with new atrial fibrillation is started on
warfarin 5 mg PO nightly. Current meds: trimethoprim-
sulfamethoxazole (for UTI started 2 days ago). INR today is 1.6
(target 2–3). Which is the most appropriate nursing action now?
A. Give the 5 mg dose and recheck INR in 2 weeks.
B. Hold warfarin today and contact prescriber to consider
lowering dose or monitoring INR closely.
C. Give warfarin and instruct patient to avoid green leafy
vegetables.
,D. Change TMP-SMX to nitrofurantoin without contacting
provider about warfarin.
Correct Answer: B
Rationales
Correct (B): TMP-SMX can potentiate warfarin effect by
inhibiting warfarin metabolism and displacing protein binding,
increasing bleeding risk. Holding the dose and contacting the
prescriber for dose adjustment and more frequent INR checks is
the safest immediate nursing action.
A: Giving the dose without addressing the interacting antibiotic
risks excessive anticoagulation and bleeding.
C: Avoiding leafy greens is general education but irrelevant to
the acute drug–drug interaction and does not address
immediate safety.
D: Changing antibiotics is a prescriber decision; acting without
contacting provider is outside nursing scope and still requires
INR monitoring.
Teaching point: TMP-SMX increases warfarin effect — hold dose
and notify prescriber; monitor INR frequently.
Citation: Vallerand, A. H., & Sanoski, C. (2025). Davis's Drug
Guide for Nurses (19th ed.). [Drug Interactions; Detecting and
Managing Adverse Drug Reactions].
2
,Drug Reference: Gentamicin — Aminoglycoside Antibiotic —
Renal Impairment & The Pediatric Patient
Stem: A 4-year-old with complicated UTI is prescribed
gentamicin IV q8h. Pre-dose trough level is 2.4 µg/mL
(therapeutic trough goal <1 µg/mL), BUN 28 mg/dL, Cr 0.6
mg/dL (baseline 0.3). Temperature 38.5°C. What is the next
nursing action?
A. Administer scheduled dose and repeat trough in 24 hours.
B. Hold dose and notify prescriber to adjust dosing interval and
obtain repeat levels.
C. Give the dose and schedule a nephrotoxic monitoring sheet
for tomorrow.
D. Administer dose and request an audiology consult after
therapy.
Correct Answer: B
Rationales
Correct (B): Elevated trough and rising creatinine indicate
accumulation and nephrotoxicity risk in a child; holding dose
and contacting prescriber for dosing interval adjustment and
repeat levels prevents further toxicity.
A: Administering despite supratherapeutic trough risks
worsening renal injury and ototoxicity.
C: Monitoring later without immediate action fails to address
current supratherapeutic level.
D: Audiology is appropriate for ototoxicity monitoring, but
immediate holding/adjusting dose is higher priority.
, Teaching point: High gentamicin troughs + rising creatinine →
hold, notify prescriber, adjust interval and monitor levels.
Citation: Vallerand, A. H., & Sanoski, C. (2025). Davis's Drug
Guide for Nurses (19th ed.). [Renal Impairment; The Pediatric
Patient].
3
Drug Reference: Methotrexate — Antimetabolite,
Antirheumatic/Antineoplastic — Females of Reproductive
Potential & REMS Overview
Stem: A 29-year-old woman with severe psoriasis is starting
methotrexate weekly. She reports irregular contraception use.
Which nursing action is highest priority before administering
the first dose?
A. Administer and advise contraception starting next menstrual
cycle.
B. Withhold medication and ensure reliable contraception and a
negative pregnancy test.
C. Give medication and schedule monthly pregnancy tests.
D. Advise abstinence but give medication as ordered.
Correct Answer: B
Rationales
Correct (B): Methotrexate is teratogenic; for females of
reproductive potential it is contraindicated without reliable
