Anti-Microbial Adverse Effects (Lecture Notes)

Question 1

Why do you see few drug-drug interactions with the penicillins?

Answer 1

Metabolism of Penicillin occurs in the Kidney

Question 2

What other ß-lactam drug are you somewhat likely to be allergic to if you are allergic to Penicillin?

Answer 2

Cephalosporins

Question 3

Why do you suspect G.I. upset is a problem with penicillin?

- what more serious problem can be caused?

Answer 3

Penicillin can disrupt the Microflora causing C. Diff infections

Question 4

What are some weird effects of penicillin?

- what patient population is this typically seen in?

Answer 4

• Platelet function is inhibited (bleeding risk)
• Blood Procrazia
• Muscle membrane issues with Innervation
• Interference with oral contraceptives

*Mostly this is seen in people with renal issues or those who are genetically predispositiond

Question 5

Why do penicillins sometimes cause oral contraceptives to be ineffective?

Answer 5

**Rooted in Microflora Destruction

Typically girl takes oral contraceptive and the following happens:
1. 1st pass metabolism occurs and Drug is pushed off into bile

2. Bile is secreted into the colon and bacteria in the colon reverse the modifications that were made on the drug by the liver.
3. Drug re-enters the blood and the effect of Birth contol is sustained

Question 6

When is the major difference in areas accessible with penicillins and cephalosporins?

Answer 6

Penicillins can’t penetrate the BBB and Cephalosporins Can - This can cause issues

Question 7

Why might cephalosporins cause an alcoholic to stop drinking for a day or two?

Answer 7

Can cause a Disulfuram (antidose) -like effect…This is a drug given to alcoholic so that Acetyladehyde accumulates and they vomit and get super hungover feeling

Question 8

What are some weird effects you might see with Cephalosporins?

Answer 8

• SIEZURES (from CNS penetration)
• Serum Sickness

Less distinctive effects:

• Thrombotic Effects with drug at the injection site
• GI distress if taken orally
• Blood issues

Question 9

What is the major difference between imipenem and meropenem?

Answer 9

Imipenem is known to cause CNS defects

Question 10

Besides Red Man sydrome what other side effects make vancomycin unique?

Answer 10

• Peripheral Neuropathy

- Renal Elimination Issues

Question 11

What drug is known to cause Rhabdomyolysis?

- what indicates that this is happening?

Answer 11

Rhabdomyolysis results from DAPTOMYCIN (and other similar drugs) causing damage to the membrane of muscle tissue CAUSING ELEVATED CPK!

Question 12

What are some classic adverse affects of Tetracycline?

Answer 12

• Tooth Staining

- Black Tongue (w/ tobacco use and bad hygiene)

Question 13

Protein synthesis inhibitor is known to cause vertigo?

Answer 13

Minocycline

Question 14

Rate the macrolides from greatest to least amount of Drug-Drug interactions?
- what causes these problems?

Answer 14

• Lots of drug-drug interactions because these work on CYP3A4 and bind SEMI-PERMINENTALLY

1. Erythromycin and Telrithromycin (MOST)
2. Clarithromycin
3. Azithromycin (LEAST)

Question 15

What are some adverse affects of macrolides?

Answer 15

• Hearing Loss
• QT prolongation (not terrible, but you don’t want to give with other drugs that elongate QT)
• Photosensitivity

Question 16

What advese affect is common with both macrolides and tetracyclines?

Answer 16

Photosensistivity

Question 17

What is your main concern with synpristin and Dalfopristin?

Answer 17

• Cyp Drug-Drug interactions

Question 18

What is your main concern with giving someone Clindamycin?

Answer 18

• Hepatic Dysfunction can be caused by these drugs

Question 19

What drug is known to cause Gray Baby syndrome?

- why does it cause this?

Answer 19

Chloramphenicol
- 90% is glucuronidated and Eliminated in the stool in normal people, in babies it accumulates in the liver causing SEVERE HEPATIC dysfunction

Question 20

What is another severe adverse affect of Chloramphenicol outside of gray baby syndrome?

Answer 20

• Serious Blood Dyscrasia

* *Aplastic Anemia

Question 21

You are given a drug that causes Optic n. Neuropathy (loss of vision) and causes Serotonin Syndrome. What drug is this?

Answer 21

Linezolid

Note: Serotinin syndrome may manifest as dilated pupils, muscle rigidity, confusion, or loss of coordination.

Question 22

What is the blackbox warning on aminoglycosides?

- what should you do to monitor these affects?

Answer 22

• Neuro and Ototoxicity
• Nephrotoxicity
• Neuromuscular Blockage

• Measure Effects by:

• Hearing Tests
• Serum Creatinin
• BUN

Question 23

What are the symptoms of a patient experiencing neuromuscular blockage as a result of taking aminoglycosides?

Answer 23

• Muscle Paralysis b/c the Neuron can’t Innervate the Muscle

- This can progress to RESPIRATORY paralysis

Question 24

What is a primary adverse reaction of TMX-SMX (Cotrimoxazole)?

Answer 24

Allergic Reactions, especially in people with HIV

Question 25

A patient goes on antibiotic therapy and a month later experiences tendonitis followed by tendon rupture. What drug do you suspect the patient was taking?
- what patients are especially susceptible to this adverse effect?

Answer 25

• Patient was most likely taking a Fluroquinolone like Ciprofloxacin

Vulnerable Populations
• Transplant Patients
• People on Coriticosteroids
• Older People

Question 26

What protein exists at the BBB and controls influx of drug into the CSF and brain?

Answer 26

P-gp (p-glycoprotein)

Question 27

What are some people who might have a compromised BBB?

- why?

Answer 27

Football Players/anyone with Chronic Inflammation

why?
• Inflammation inhibits p-gp
• less CSF so less outflow pushing the drug out of the CNS cavities

Question 28

Why can’t you just jack up the dose to get drug across the BBB?

Answer 28

You’ll get outside of the Therapeutic Window

Question 29

How does knowing that a works on the basis of concentration dependent killing, rather than time dependent killing change how you dose?

Answer 29

Concentration Dependent Killing:

• One High Dose Periodically
• Jacks up the Blood Conc. Killing the Bug
• Can’t Keep conc. high for too long or you’ll kill pt.
• Use wide intervals

Time Dependent Killing:
- Lots of small doses to keep the drug steady for long enough to kill the bug