AMCT- DRUGS Flashcards
Benzyl Penicillin
- gram positive
- meningococci
- normally IV
- B-lactam
- disrupts peptidoglycan synthesis
Amoxicillin + Ampicillin
- oral absorption good
- better at attacking gram negative organisms than benzyl penicillin but 20-30% of coliforms resistant
Co-amoxiclav
- combines amoxiclav with B-lactamase inhibitor clavulanic acid
Flucloxacillin
- B-lactamase resistant
- first line of treatment for staph infections
Methicillin
-similar to flucloxacillin in that it is B-lactamase resistant. used to represent flucloxacillin in the lab, but is not used clinically. (MRSA = Methicillin resistant staphylococcal aureus)
Piperacillin
- broad spectrum penicillin with gram negative cover
- active against pseudomonas
- has anti-anaerobic activity so it can cover serious intra-abdominal infection
- now commonly used with B-lactamase inhibitor tazobactum, which together combine to make tazocin (commonly referred to as “pip/taz”)
Imipenem + Meropenem
- carbapenems (close relatives of penicillin)
- have widest spectrum of all ‘penicillin type’ antibiotics
- active against most bacteria including anaerobes
Cephalosporins
- 3 generations
- gram positive resistance increasing
- gram negative activity increasing
- use of cephalosporins has decreased recently as they appear to encourage C.Diff infections
Gentamicin
- amino-glycoside
- gram negative activity including pseudomonas
- most staph sensitive
- strep not sensitive
- high potential toxicity
Vancomycin, Teicoplanin
- glycopeptides
- only active against gram positive
- aerobic and anaerobic activity
- levels of vancomycin must be monitored for toxicity
Clarithromycin/ erythromycin
- mainly active against gram positive
- often used as an alternative to penicillin for patients with a hypersensitivity to penicillin
- macrolides
Azithromycin
- macrolide
- single dose chlamydia treatment
Ciprofloxacin
- quinolone
- nearly all gram negative organisms
- oral treatment for pseudomonas
- can’t be used in children as in inhibits nucleic acid synthesis
Metronidazole
effective against gram negative and positive organisms
Fusidic acid
- used only as an anti-staphlococcal drug
- diffuses well into bone and tissue
trimethoprim
- urinary infection
- combined with sulfamethoxazole to make co-trimoxazole, sometimes used in chest infections as it does not predispose C.Diff infections
Tetracyclines
- broad spectrum
- inhibit protein synthesis
- some genital/ respiratory tract infections
- should not be given to pregnant women or children U12 as they are deposited in teeth and bones
Clindamycin
- gram positive
- anaerobes
- very good tissue penetration
linezolid
- new agent with activity against MRSA
- oral
- can cause bone marrow suppression
daptomycin
- gram + organisms
- may combat MRSA
Nalidixic acid
- UTI agent
- gram negative (coliforms) only
Nitrofurantoin
- UTI agent
- most gram negative
- some gram positive
Amphotericin B
- IV for serious systemic yeast and other fungal infections
- highly toxic
- polyene
Nystatin
- polyene
- topical and oral use
- fungal skin infections
Why are polyenes toxic
Because they target ergosterol present in the cell wall of fungi, resulting in increased permeability. However they also bind to other sterols e.g. cholesterol in mammalian cells.
Fluconazole
- oral and parental treatment of yeast infections
- no activity against filamentous fungi
- some resistant among candida species emerging
- azole (suppresses ergosterol synthesis)
Itraconazole
- active against yeast and filamentous fungi
- azole
Voriconazole
- used to treat aspergillosis
- azole
Terbinafine
- clinical use is primarily against dermatophyte infections of the skin and nails (e.g. athletes foot, ringworm)
- mild infections treated topically, more serious orally
- allylamine
- suppresses ergosterol synthesis
Caspofungin, mycafungin, anidulafungin
- inhibits gluten polysaccharide synthesis
- fungicidal against candida species
- fungistatic against aspergillus species
- normally only used upon specialist advice
- echinocandins
Aciclovir
- anti-herpes
- nucleoside analogue
- must be converted to its active form by an enzyme that is only coded for in the viral genome, hence it can be specific for virus infected cells
- IV form given to treat serious infections
- cold sores can be treated topically or orally
Famciclover, valaciclovir
- oral agents
- better bioavailability than aciclovir
Ganciclovir, valganciclovir
- nucleoside analogue
- active against CMV
- toxic
- IV infusion
- largely restricted to life or sight threatening infections in the immunocompromised
Foscarnet
- used when herpes virus is resistant to nucleoside analogues
- highly nephrotoxic
- IV only
Cidofovir
CMV only when other drugs are inappropriate
Zidovudine (AZT, ZDV)
- anti-HIV
- nucleoside analogue
- interferes with action of reverse transcriptase
- virulstatic
- high incidence of side effects when being administered by itself
Administration of anti-HIV drugs
combination therapy of zidovudine with at least 3 other drugs is normal practice.
drugs are selected which are active on at least two different stages of HIV replication
Nevirapine
Non-nucleotide reverse transcriptase inhibitor
Saquinavir
Protease inhibitor
Interferon-alpha
- produced by genetic engineering
- low response rate
- serious side effects
- normally subcutaneous infection
- combination therapy with oral ribavarin is common treatment for chronic Hep C
Lamivudine
- nucleoside analogue
- when combined with adefovir, dipivoxil is suitable for chronic Hep B
- can be given orally
Zanamavir, oseltamivir
- influenza A or B < 48 hours after onset of symptoms, or post exposure prophylaxis
Ribavarin
- nucleoside analogue
- treatment of severe respiratory syncytial virus (RSV)
- must be inhaled as a very fine spray to reach site of infection in lungs so administration is difficult
- used in combination treatment for Hep C
