other drugs

Question 1

what is the cephalosporins’ broad spectrum

Answer 1

Activity against transpeptidases of different bacterial species

Question 2

what are the features of aminoglycosides

Answer 2

Bactericidal
Gentamicin
Nephrotoxicity, ototoxicity

Question 3

what are the features of tetracylines

Answer 3

Bacteriostatic – broad spectrum
Doxycycline, minocycline
Phototoxicity, chelation* of metal ions

Question 4

what does phototoxic mean?

Answer 4

toxic effect triggered by exposure to light chemically induced skin irritation

Question 5

what drugs are inhibitors of DNA replication

Answer 5

Quinolones,metronidazoles, rifampicin, antimetabolites

Question 6

what are examples of quinolones?

Answer 6

Ciprofloxacin, nalidixic acid, norfloxacin, ofloxacin

Question 7

what do quinolones do?

Answer 7

Inhibition of enzymes (DNA gyrases) needed for supercoiling, replication and separation of circular bacterial DNA - Rapid bacterial cell death
˃˃G-, G+, anaerobes, Mycoplasma, Chlamydia (depending on the quinolone)

Question 8

what are the uses of quinolones

Answer 8

urinary tract infections (not first line), pseudomonal infection, gastrointestinal infections, prostatitis, sexually transmitted infections

Question 9

what are DNA gyrases

Answer 9

essential (and mainly) bacterial enzymes that catalyse the ATP-dependent negative supercoiling of double-stranded closed-circular DNA. Gyrase belongs to a class of enzymes known as topoisomerases that are involved in the control of topological transitions of DNA

Question 10

what are metronidazoles

Answer 10

Prodrug – only anaerobic organisms can metabolite to its active form
Metabolites produced are toxic to DNA – bactericidal
Considered potentially mutagenic, carcinogenic, and teratogenic

Question 11

what is rifampicin

Answer 11

Bactericidal – Mycobacteria (M. tuberculosis, M. leprae)
Binds to RNA polymerase → inhibits mRNA synthesis

Question 12

what does mutagenic mean

Answer 12

capable of inducing mutation or increasing its rate

Question 13

what does teratogenic mean

Answer 13

may produce physical or functional defects in the human embryo or foetus/ potential to cause malformations

Question 14

what is synergistic association

Answer 14

interaction or cooperation of two or more organisations, substances, or other agents to produce a combined effect greater than the sum of their separate effects

Question 15

what are antimetabolites

Answer 15

drugs that are chemically similar to naturally occurring metabolites, but differ enough to interfere with normal metabolic pathways

Question 16

what happens when sulfonamide and trimethorpin interact

Answer 16

Sulfonamide + trimethoprim → synergistic** association
Act in the same pathway (different stages) - Synthesis of tetrahydrofolate

Question 17

features of sulfanomides and trimethoprim

Answer 17

Bacteriostatic
Co-trimoxazole may be bactericidal and resistance is not common

Question 18

what are mechanisms of antibiotic resistance

Answer 18

Inactivation or modification of the antibiotic
Alteration of microbial enzymes that transform pro-drugs to the effective moieties
Alteration of the target
Reduced uptake of the antibiotic
Enhanced export of the antibiotic (efflux pumps)
Development of alternative pathways

Question 19

what ways has antibiotic resistance impacted the treatment of patients

Answer 19

Promoting the development of new antibiotics and new diagnostic tests for resistant bacteria
NICE guidance