UNIT 10 Sulfonamide

Question 1

What is the peak and trough?

Answer 1

Peak - highest concentration of the drug in the blood stream

Trough- The trough drug level is the lowest plasma concentration of a drug, and it measures the rate at which the drug is eliminated

Question 2

When are Peak labs drawn for an IV medication?
A. 30-60 minutes after drug administration
B. 1 hour - 2 hours after drug administration
C. immediately after drug administration
D. immediately before the next dose of a medication

Answer 2

A. 30-60 minutes after drug administration

If the drug is given intravenously, the peak time is usually 30 to 60 minutes after the infusion is complete.

If the drug is given intramuscularly, the peak time is usually 2 to 4 hours after injection.

If the drug is given orally, the peak time is usually 2 to 3 hours after drug administration.

Question 3

When would you pull a Trough lab when a patient has been receiving antibiotic medication?
A. immediately before the next dose of drug regardless of route of administration.
B. just after the next dose of drug regardless of route of administration.
C. 30 -60 minutes after drug administration
D. 1 hour before the next dose of the antibiotic medication

Answer 3

A. immediately before the next dose of drug regardless of route of administration.

The trough drug level is the lowest plasma concentration of a drug, and it measures the rate at which the drug is eliminated. Trough levels are drawn just before the next dose of drug regardless of route of administration.

Question 4

Is Trimethoprim- sulfamethoxazole an Antibiotic?

A. Yes
B No

Answer 4

A. Yes

Question 5

What can Trimethoprim- sulfamethoxazole be used for?

Answer 5

Synergistic effect
Both drugs together in one compound cause bacterial
resistance to develop much more slowly.
Seeing it used for MRSA
Urinary infections (also in chapter 48)
Alternative therapy for patients allergic to penicillin

Route
Oral, IV, topical, ophthalmic

Question 6

What are the side effects of Trimethoprim- sulfamethoxazole ?

Answer 6

GI distress,
stomatitis-inflamed or sore mouth
Photosensitivity

Question 7

What are the adverse effects of Trimethoprim- sulfamethoxazole ?

Answer 7

Hypoglycemia
Blood dyscrasias-RBC’s, WBC’s, platelets
Crystalluria(CRYSTALS IN URINE) can lead to Renal failure
Stevens-Johnson syndrome

Question 8

Contraindications of Trimethoprim- sulfamethoxazole ?

Answer 8

Renal or liver disease
Anemia

Caution
◦ Older adults
◦ Diabetes

Interactions
Increase bleeding with warfarin
Increases effect of hypoglycemic
Increases digoxin level

Question 9

Nursing Interventions for Trimethoprim- sulfamethoxazole ?

Answer 9

Obtain C & S
Administer with full glass of water
Increase fluid intake to at least 2000 mL/day.
Monitor I & O
Monitor VS
Monitor for bleeding, CBC, and renal function.
Monitor for rash, superinfection.
Avoid during third trimester.
Best given on an empty stomach

Question 10

Patient teaching for Trimethoprim- sulfamethoxazole ?

Answer 10

Increase fluids to several quarts a day
Do not take antacids with med
Warn patient if allergic to other sulfa drugs may be
allergic to this one (oral hypoglycemics – sulfonylureas)
Teach to side effects and how to minimize them
Teach to adverse reactions to report such as bruising or
bleeding
Wear sunglasses and sunblock when outdoors(PHOTOSENSITIVITY)
How do we know it worked?

Question 11

Topical and Ophthalmic
Sulfonamides

Answer 11

Topical use of sulfonamides can cause
hypersensitivity reactions; they are infrequently
used.

Silver sulfadiazine: Used in the treatment of burns
and sometimes skin ulcers

Question 12

When teaching a patient about trimethoprim-
sulfamethoxazole (TMP-SMZ), the nurse gives
highest priority to teaching the patient to
A. increase fluid intake.
B. report signs of ringing in the ears or loss of hearing.
C. expect the color of their urine to change to a reddish
orange.
D. take this drug with dairy products or antacids to
protect the stomach

Answer 12

Answer: A
Rationale: Fluid intake should be increased to at least 2000 mL/day when
taking sulfonamides to prevent crystalluria. Ototoxicity is not a common
adverse effect of sulfonamides. The urine will not change colors. Dairy
products or antacids should not be taken at the same time as sulfonamides
because they decrease absorption

Question 13

A patient is ordered to receive co-
trimoxazole/TMP-SMZ (Bactrim). This
medication is a combination of two medications
that are
A. antagonistic.
B. additive.
C. synergistic.
D. contraindicated.

Answer 13

Answer: C
Rationale: A synergistic effect results in increasing the desired drug
response

Question 14

A. When used with sulfonylureas, sulfonamides
decrease the hypoglycemic effect.
B. When sulfonamides are used with warfarin, the
anticoagulant effect is decreased.
C. Sulfonamides must be taken with antacids to
prevent gastric ulceration.
D. Patients on sulfonamide therapy need to increase
their fluid intake.

Answer 14

D. Patients on sulfonamide therapy need to increase
their fluid intake.

Answer: D
Rationale: Patients taking sulfonamides need to drink several quarts of
fluid daily to avoid the complication of crystalluria. These drugs increase
the hypoglycemic effect of sulfonylureas, increase the anticoagulant
effect of warfarin, and should not be taken with antacids because antacids
decrease the absorption rate of the drug.