Antibiotics

Question 1

Aminoglycosides

Answer 1

Examples of Aminoglycosides:
Streptamycin, Gentamycin.

Inhibits protein synthesis via binding to 30s ribosome subunit.

For gram + and -

Side effects include nephrotoxicity and ototoxicity.

Used for UTI, endocarditis, topical skin infection, pneumonia.

Question 2

Cephalosporins

Answer 2

Examples of Cephalosporins:
1st gen: cefazolin 2nd gen: cefotetan 3rd gen: cefotaxime, ceftriaxone, cefixime 4th gen: cefepime 5th gen: ceftaroline.

Inhibits cell wall synthesis.

Gen dependent for + or -

Do not give with calcium solutions- causes precipitation in lungs and kidneys. Side effects include hypersensitivity, superinfection with enterococci, enterobacter or candida.

Gens 1-3 cover URT, skin and soft tissue infections, CAP, sinusitis.
Gen 3 covers CAP, bacterial meningitis, UTI, anogenital gonorrhea, abdo/pelvic pain. Gram - focus.
Gen 4 has pseudomonas cover and Gen 5 has really broad spectrum of use.

Question 3

Carbapenems

Answer 3

Examples of Carbapenems:
doripenem, imipenem, meropenem.

Inhibits cell wall synthesis.

Can inhibit betalactamase- used as last line for + and -.

Side effects include GI upset, rash, allergy and seizures if RF.

Used for UTIs, meningitis, sepsis, bone and pelvo/abdo infections.

Question 4

Penicillins

Answer 4

Examples of penicillins:
amoxicillin, piperacillin, flucloxacillin. Are often combined with a betalactamase inhibitor = coamoxiclav/piptaz.

Inhibits cell wall synthesis.

Gram + and -.

Side effects can be hypersensitivity, neurotoxicity/seizures when intrathecal.

Used for endocarditis, skin/soft tissue infections, URTI/pneumonia, neurosyphillis.

Question 5

Tetracyclines

Answer 5

Examples of tetracyclines:
tetracycline and doxycycline.

Inhibits protein synthesis by binding to 30s ribosomal subunit.

Gram + and - but not used for staph and strep.

Side effects include GI, renal, reversible liver toxicity, teeth staining, impaired fetal bone growth (not for pregnant or under 8).

Used for anthrax, c.tetani, atypical CAP.

Question 6

Quinolones

Answer 6

Examples of quinolones:
ciprofloxacin, levofloxacin, moxifloxacin.

Inhibits DNA gyrases.

For gram + and - (more +).

Side effects can include cartilage toxicity, Achilles tendon rupture, peripheral neuropathy, pseudomembranous colitis from c.dif.

Used for atypical pneumonia, UTI, gastroenteritis, osteomyelitis.

Question 7

Macrolides

Answer 7

Examples of macrolides include:
clarithromycin, erythromycin.

Inhibits protein synthesis via binding to 50s ribosomal subunit.

Target gram +.

Side effects include GI upset, hypersensitivity, CYP450 inhibition ( not azithromycin), (and for erythromycin:) jaundice and QT prolongation.

Used for resp/sinus/skin infections and chlamydia.

Question 8

Sulfonamides

Answer 8

Examples of sulfonamides:
sulfamethoxazole and trimethoprim.

Inhibits folic acid production.

Targets gram + and - and MRSA.

Side effects include hypersensitivity/SJS, nephrotoxicity, hyperkalemia, neutropenia, kernicterus.

Used for MRSA and cystitis due to e.coli.

Question 9

Glycopeptides

Answer 9

Examples of glycopepsides:
vancomycin.

Inhibits cell wall synthesis.

Treats gram +.

Side effects include nephrotoxicity, ototoxicity, hypotension and flushing.

Used for MRSA, endocarditis, pseudomembranous colitis due to c.diff.

(gentamycin is an aminoglycoside, but also damages kidneys and ears)