Lec2

Question 1

Drugs that inhibit bacterial protein synthesis

Answer 1

1.Macrolides
2.clindamycin
3.tetracyclin
4.aminoglycosides

Question 2

Macrolides examples

Answer 2

1.Erythromycin 2.clarithromycin 3.Azithromycin

Question 3

Macrolides mechanism of action

Answer 3

Bacteriostatic
Inhibit 50s ribosome subunit -> lead to misreading of mRNA->Inhibit bacterial protein synthesis

Question 4

Macrolides root of administration

Answer 4

Oral

Question 5

Erythromycin distributes well to all body fluid except…….

Answer 5

CSF

Question 6

Root of excretion for erythromycin and azithromycin

Answer 6

In the Bile as active drugs

Question 7

Erythromycin may used as a replacement for penicillin why?

Answer 7

It’s used for patient who have penicillin allergy Cuz It’s effective against many of the same organisms as penicillin

Question 8

When does the erythromycin is used?

Answer 8

In gastroparesis cuz it promotes gastric emptying

Question 9

Drug has the same effect as erythromycin and also effective against haemophilus influenza

Answer 9

Clarithromycin

Question 10

Proffered therapy for urethritis caused by chlamydia trachomatis

Answer 10

Azithromycin

Question 11

Adverse drug reactions of macrolides

Answer 11

-GIT upset nausea, vomiting, abdominal pain & diarrhoea
-ototoxicity: associated with erythromycin, especially at high dose

Question 12

Contraindications of macrolides

Answer 12

It can accumulate in the liver in the patient who have hepatic failure

Question 13

Drug to drug interaction of macrolides

Answer 13

Question 14

Clindamycin mechanism of action

Answer 14

Same as macrolides

Question 15

Root of administration of clindamycin

Answer 15

IV & oral-limited by gastrointestinal tolerance-

Question 16

Distribution of clindamycin drugs in the body

Answer 16

Well in all body fluid and boon, poor entry into the CSF

Question 17

Clindamycin root of excretion

Answer 17

Bile

Question 18

Accommodated clindamycin occur in

Answer 18

Severe renal impairment or hepatic failure

Question 19

Clindamycin used against….

Answer 19

Gram positive organisms, including MRSA and streptococcus, and anaerobic bacteria

Question 20

Adverse drug reactions to clindamycin

Answer 20

1.Skin rashes
2 Diarrhea, which may represent a serious pseudomembranous colitis caused by overgrowth of C. difficile.

Question 21

C. Difficile treatment

Answer 21

Oral vancomycin

Question 22

Tetracyclines examples

Answer 22

Doxycycline or tetracycline

Question 23

Mechanism of action

Answer 23

It has the same effect as macrolides but it bind to the 30s subunit of bacterial ribosome not the 50s subunit

Question 24

Root of administration of tetracycline

Answer 24

Oral

Question 25

Distribution of tetracycline antibiotics

Answer 25

Penetration into most body fluids is adequate , cross the placental barrier and concentrate in fetal bones and teeth

Question 26

Root of elimination of tetracyclines antibiotics

Answer 26

Primarily in urine but doxycycline eliminated via the bile

Question 27

Which drug is preferred in tetracycline for renally compromised patients

Answer 27

Doxycycline (excretion via bile into the feces)

Question 28

Adverse drug effects of tetracyclines

Answer 28

Gastric discomfort -commonly via irritation of the gastric mucosa. Phototoxicity -if exposed to ultraviolet rayes Vestibular dysfunction -dizziness,vertigo and tinnitus

Question 29

Contraindications of tetracycline antibiotics

Answer 29

Don’t se if -pregnant -breast-feeding Women -less than 8 years of age

Question 30

Aminoglycoside examples

Answer 30

Streptomycin, amikacin or gentamicin

Question 31

Mechanism of action for Aminoglycosides

Answer 31

Same as tetracycline

Question 32

Root of administration of Aminoglycosides

Answer 32

IV or IM

Question 33

Distribution of Aminoglycosides in the body

Answer 33

Poor penetration to CSF also it has a good entry to inflamed tissues

Question 34

Root of excretion

Answer 34

Via glomerular filtration

Question 35

Adverse drug effect for Aminoglycosides

Answer 35

Nephrotoxicity ototoxicity (due to auditory or vestibular nerve damage)

Question 36

Drug to drug interactions for Aminoglycosides

Answer 36

Ototoxicity is enhanced by loop diuretics(e.g.furosemide)

Question 37

Drugs that inhibit bacterial nucleic acid synthesis

Answer 37

1. Quinolones 2. Rifampcin

Question 38

Quinolones examples

Answer 38

Levofloxacin ciprofloxacin

Question 39

Mechanism of action of quinolones

Answer 39

Bactericidal Inhibit DNA gyrase (bacterial topoisomerarse||)-> relaxation of supercoiled DNA(promoting DNA strand breakage) -> inhibit bacterial nucleic acid synthesis

Question 40

DNA gyrase

Answer 40

DNA gyrase : preserve the state of supercoiling in replicating and non-replicating bacterial chromosomes )

Question 41

Distribution of quinolones drug in the body

Answer 41

Distribute well in all body fluids and tissues

Question 42

Root of excretion for quinolones

Answer 42

Renally (dosage adjustment is needed in cases of renal failure)

Question 43

Adverse drug effect for quinolones

Answer 43

-Phototoxicity (if exposed to uv) -Tendinitis or tendon rupture

Question 44

Drug to drug interactions for quinolones

Answer 44

Inhibit hepatic drug metabolism & prolong action of theophylline and warfarin

Question 45

Rifampcin mechanism of action

Answer 45

Bactericidal Inhibit the DNA-dependant RNA polymerase of mycobacterium TB-> prevent transcription of DAN into mRNA

Question 46

Why rifampicin has no effect in some of the mycobacteriumTB

Answer 46

The mycobacterium TB become resistant to the drug because of a mutation in it’s DNA-dependant RNA polymerase gene

Question 47

Root of administration for Rifampicin

Answer 47

Oral

Question 48

Distribution of

Question 49

Distribution of the rifampicin in the body

Answer 49

Widely distributed to all body fluids and organs(including the CSF)

Question 50

Potent liver enzymes inducer

Answer 50

Rifampicin

Question 51

Root of elimination

Answer 51

Primarily through the bile and into the feces a small percentage is cleared in the urine

Question 52

Adverse drug effect of rifampicin

Answer 52

-Red-orange secretions ( tears – urine -....) -Thrombocytopenia -Hepatotoxicity (Hepatitis)

Question 53

Drug to drug interactions of rifampicin

Answer 53

Hepatic enzyme inducer: increase metabolism of warfarin, phenytoin, oral contraceptive pills

Question 54

Antibiotics antagonism

Answer 54

indicates that decreased anti-microbial effect of a drug when combined with another, leading to decreased response

Question 55

Mechanisms of antagonism include:

Answer 55

-Decreased bactericidal activity by bacteristatic agent e.g. tetracycline and Penicillins -Increased enzymatic inactivation e.g. ampicillin decrease pipracillin activity

Question 56

Rule of right (5 Rs)

Answer 56

1.right drug 2. Right dose 3. Right route 4. Right time (interval and duration) 5. Right patient