Tetracyclines: Exam 1 COPY

Question 1

What is the MOA of tetracyclines?

Answer 1

Inhibit protein synthesis by reversibly binding to the 30S subunit of the bacterial ribosome

Question 2

Tetracyclines are mostly effective against gram:

Answer 2

Positive organisms

Question 3

How well is doxycycline absorbed?

Answer 3

It’s absorbed about 95%-100% (the highest of the tetracyclines)

Question 4

How well is tetracycline absorbed?

Answer 4

It’s absorbed about 60-70% (the highest of the tetracycline

Question 5

General instructions for taking tetracyclines by mouth include:

Answer 5

Take on empty stomach

Question 6

Tetracyclines interact with these foods/OTC drugs:

Answer 6

Antacids, dairy foods, iron salts, and sodium bicarbonate

Question 7

If taking antacids or dairy products with tetracyclines an individual should do this:

Answer 7

Separate doses by 2 hours, and take tetracycline first

Question 8

What are drugs which interact with tetracyclines?

Answer 8

Warfarin
Barbiturates
Carbamazepine
Hydantoins
Cimetidine
Digodix
Lithium
PO Contraceptives
Penicillin

Question 9

Are doxycycline and tetracycline safe to give during pregnancy?

Answer 9

NO!

Question 10

How is tetracycline typically prescribed?

Answer 10

Both topically and orally to treat acne and is one of four drugs in the combination treatment of H. pylori infection

Question 11

Doxycycline is the most commonly prescribed tetracycline because it has the least:

Answer 11

amount of drug-food interactions

Question 12

How is doxycycline distributed in the body?

Answer 12

-Highly lipid soluble
-Readily penetrates body tissues and fluids
-crosses placental membranes
-Fetal plasma concentrations reach 60% of maternal serum levels

Question 13

Tetracyclines are eliminated & excreted via:

Answer 13

-The kidney via glomerular filtration
-Liver metabolism and undergo enterohepatic recirculation

Excretion: bile and feces

Question 14

Tetracyclines require dose adjustments for:

Answer 14

Renal impairment

Question 15

Tetracyclines are contraindicated in:

Answer 15

-Severe hepatic dysfunction
-pregnancy
-children younger than 8 years old
-severe renal impairment

Question 16

Doxycycline is eliminated via:

Answer 16

30-42% unchanged in urine; remainder excreted in bile & feces

Question 17

Tetracycline is eliminated via:

Answer 17

20%–55% unchanged in urine

Question 18

What does current evidence say about lactation when using tetracycline?

Answer 18

Tetracycline: is excreted in breast milk; however, the it is compatible with breastfeeding because the serum concentrations were below detectable levels and there was no evidence of teeth staining

Question 19

What does current evidence say about lactation when using doxycycline?

Answer 19

Doxy is excreted in breast milk; however, because milk levels are low and absorption is inhibited by the calcium in breast milk, a short course is considered safe during lactation

Question 20

Why shouldn’t tetracyclines be given to children?

Answer 20

These drugs form a stable calcium complex in any bone-forming tissue, decreasing bone growth. They also may cause permanent yellow/gray/brown discoloration of deciduous and permanent teeth

Question 21

Doxycycline is the primary drug of choice for:

Answer 21

Ehrlichiosis and rickettsial infections (e.g., Rocky Mountain spotted fever, typhus, Q fever, and trench fever caused by B. quintana)

Question 22

What are some ADR when taking tetracyclines?

Answer 22

GI Upset (anorexia, N/V/D)
Esophageal ulcers
C. Diff
Pseudotumor cerebri (benign intracranial hypertension)
Hepatotoxicity
Superinfection

Question 23

What are dermatological reactions associated with taking tetracyclines?

Answer 23

1. Photosensitivity: manifested by an exaggerated sunburn, and a maculopapular/ erythematous rash.
2. Severe skin reactions: Stevens–Johnson syndrome, toxic epidermal necrolysis

Question 24

What are the primary drug-drug interactions associated with tetracyclines?

Answer 24

Divalent and trivalent cations found in antacids, iron salts, sevelamer, magnesium-containing laxatives, and zinc supplements

Question 25

If the patient needs to eat while taking tetracyclines, give these instructions:

Answer 25

Administer tetracyclines 1 hour before or 2 hours after meals

Question 26

To prevent esophageal irritation, give these instructions:

Answer 26

Do not take tetracyclines at bedtime and administer with a full 8 oz glass of water

Question 27

Instructions on how to avoid phytotoxicity reactions when taking tetracyclines:

Answer 27

Wear sunscreen, hats, and protective clothing if it is necessary to be in the sun for more than a few minutes

Question 28

What are signs of hepatotoxicity from taking tetracyclines?

Answer 28

Upper abdominal pain, nausea, vomiting, dark urine, clay-colored stools, or yellowing of skin or eyes

Question 29

What are signs of a superinfection that should be reported?

Answer 29

Hoarseness, glossitis, sore throat, dysphagia, or vaginal itching and discharge