Anti-infectives Flashcards
Azole Antifungals
C- Azole antifungal, impairs synthesis of fungal cell wall
I- Clotrimazole- fungal skin infections, vaginal candidiasis (only topical available)
Fluconazole- mucocutaneous candidiasis, vaginal thrush, Candida infection with susceptitble organism, cryptococcosis, coccidiodomycosis, histoplasmosis, prophylaxis in immunocompromised, tinea corporis, crusis or pedis resistant to topical, onychomycosis
Miconazole- oral thrush treatment and prophylaxis, fungal skin infections (only topical available)
D-
Clotrimazole- apply bd- tds
Fluconzaole- varies for indication (max 800mg for systemic candidiasis) commonly 50-200mg once daily usual max 400mg. Vaginal thrush- 150mg stat
Miconazole- oral qid, topical- bd
M- resolution of fungal infection, topical-skin reaction, allergy to azole- cross reactivity,
Oral azoles- peripheral neuropathy- may worsen with long term use, LFTs- hepatotoxic, FBC-blood dyscrasias, drug interactions-common,
fluconazole- QT prolongation monitor ECG, renal dose reduction, weight loss, SJS, serum potassium
C- topical- use until symptoms resolve and then for 2 weeks after, miconazole gel- >2yo use after meals, hold in mouth for as long as possible, continue using for several days after symptom resolution, apply to dentures. Fluconazole- tell dr if you feel unusually tired, nauseous, not eating notice pale stools dark urine or yellowing of skin/eyes, ask dr/pharmacist before taking other medications, take until full course is complete
Others- Itraconazole, posaconazole, voriconazole
Fluconazole CAL- 5, 21, A, D
Amphotericin B
C- other antifungal, causes cell wall to be leaky
I-Severe systemic fungal infections, emperical treatment in febrile neutropenia unresponsive to antibacterials, Cryptococcal meningitis, oral thrush, prophylaxis post liver transplant and HIV, visceral leishmaniasis, amoebic meningitis
D- IV 3-5mg/kg once daily (max 10mg/kg). Lozenge- 1 qid for 7-14 days.
M-nephrotoxicity (CrCl, hypokalaemia, hypomag, anuria/oligouria), infusion reaction- fever, chills, hypotension, NV, BGL in diabetics (ambisome contains 900mg sucrose), iron studies and FBC (anaemia AE), resolution of fungal infection, LFTs
C- lozenge- use until symptoms resolve then for several days, use after meals/drink,
Terbinafine
C- other antifungal
I- onychomycosis, dermatophyte infection of skin, groin, feet where topical has failed, fungal skin infections
D- topical- apply od for 1 week
Oral- 250mg od treatment length depends on site of infection (eg 12 weeks for toenails)
M-psorasis or lupus erythematosus- may be exacerbated, renal dose reduction, LFTs, rash (stop treatment if hepatotoxicity or rash occurs)
C- AE- NVD abdo pain, tell dr if feeling tired nauseous not eating dark urine or pale stools yellowing of eyes or skin, nail must grow out for treatment success, take full course
Aminoglycosides
C- Aminoglycosides Abx- binds 30S ribosomal subunit causing cell membrane damage. Concentration dependent bactericidal effect.
I- Empirical treatment of serious gram -ve infections, systemic enterococcal infections (with beta-lactam or vancomycin), sensitive infections resistant to narrower spectrum Abx, Pseudomonas aeruginosa infections in CF, eye infections
Dose (ideal body weight) Gentamicin- CrCl>60 5-7mg/kg once daily CrCl 30-60 4-5mg/kg once daily Neb- 80mg bd
Tobramycin
CrCl>60 5-7mg/kg once daily
CrCl 30-60 4-5mg/kg
Neb 300mg bd for 28 days, then 28 days off then repeat
DPI (tobipod)- 112mg (4 caps) bd for 28 days then 28 days off then repeat
M- TDM- courses <48h in normal renal function do not need monitoring (use ideal body weight), serum drug level, AUC- peak (aim for Cmax 85-100) and trough levels (aim for Cmin<0.05) nephrotoxicity, CrCl ototoxicity, hearing tests, neuromuscular blockade, resolution of infection (decrease CRP and WCC)
C- if given for >7-10 days your kidneys may reduced function but should improve when drug is stopped, tell doctor if hearing or balance changes (ototoxicity can be irreversible), ensure adequate hydration,
tobipod inhaler- use bronchodilators first and change podhaler after 7 days, AE- bronchospasm (give first dose under supervision), voice change, cough, throat pain
Cephalosporins
C- cephalosporins ABx- bind penicillin binding protein which inhibits cell wall synthesis
Cefaclor-
I- acute otitis media, resp infections caused by H. influenzae, acute sinusitis
D- oral 250-500mg q8h or 375-750mg q12h CR (max 4g daily). Child 10-15mg/kg (max 500mg) q8h. Take with food, CR swallow whole
Cephalexin
I- staph and steph infection in pt with mild-moderate penicillin allergy, UTI, Epididymo-orchitis (urinary source)
D- 250mg q6h or 500mg q6-12h (max 4g daily). Child 6.25-12.5mg/kg (max 500mg) q6h. UTI prophylaxis 250mg nocte. Take irrespective of food
Cefuroxime
I - Acute sinusitis, resp infections cause by H. influenzae, Acute otitis media, Gonnococcal infections (alternative to amoxicillin)
D- 250-500mg bd (up to 1g single dose). Child 15mg/kg (max 250mg) bd. Take with food, swallow whole
M-infection resolution (CRP and WCC), renal function (reduced dose in severe impairment), allergic reactions
C- take full course, signs of allergy, see Dr for severe persistent diarrhoea,
Macrolides
C- macrolide ABx- binds 50s ribosomal subunit. also has immunomudulatory and anti-inflammatory properties
Azithromycin
I- chlamydia, strep pharyngitis/tonsilitis, CAP, MAC infection, donovanosis, typhoid, paratyphoid, travellers diarrhoea, treatment and prevention of pertussis
D- 500mg on day 1 then 500mg for 2 days 93 days total) or 250mg for 4 days. Can be extended depending on infection. 1g stat for chlamydia and travellers diarrhoea Max 1.2g in a single dose.
Clarithromycin
I- MAC, H pylori erradication, LRTI, prevention and treatment of pertussis
D- 250-500mg bd (max 1g bd)
Erythromycin
I-URTI, LRTI, rhuematic fever prophylaxis in penicillin allergy, legionaires disease, campylobacter enteritis, coral cuts, chlamydial infections, prevention and treatment of pertussis, Acne, rosacea
D- oral 1-2g daily in 2-4 doses (max 4g daily). acne/rosaecea- 250-500mg bd. Erythromycin base (eryc brand)- take 1h before or 2h after food, take with food if GI irritation occurs
Roxithromycin
I- URTI, LRTI, CAP, skin infections
D- 150mg bd or 300mg od (max 300mg/day), best absorbed on empty stomach but take with food if upsets stomach.
M- ECG (QT prolongation- more common with erythromycin and clarithromycin), drug interactions (clarithromycin and erythromycin), LFTs, GI-AE (erythromycin++), infection resolution, CRP, WCC, infantile hypertrophic pyloric stenosis if less than 7 weeks old,
C- eryth and roxith tak on empty stomach if able to tolerate or with food if not, tell dr if baby has vomiting or irritable when feeding, eryth/clarith- multiple DDI talk to dr/pharm before taking anything, finish whole course
CAL- Azithro- D Clarith-5, D Eryth- 5, 18, D Roxith-3b, D
Nitroimidazoles
C- Nirtoimidazoles, interfere with bacterial DNA synthesis
Metronidazole
I- gram +ve and -ve anaerobic infections, protozoal infections (eg giardiasis), dental infection, intraabdominal infection, aspiration pneumonia, lung abscess, bacterial vaginosis, PID, amoebiasis, eradication of H pylori (~50% of cases are resistant), rosacea, fungating wounds, C diff
D- oral 200-400mg q8-12h up to 4g daily. max IV 500mg in single dose. rectal 1g q8-12h. single stat dose 2g can be used in trichomoniasis and giardiasis
Tinidazole
I- protozoal infections (eg giardiasis, trichomoniasis), amoebiasis, bacterial vaginosis, prophylaxis in GI and gynaecological surgery
D- 1-2g daily (most indcations are 2g stat single dose), courses dont usually exceed 3-5 days
M- neurotoxcity (avoid use in epilepsy), FBC (can cause blood dyscrasia- luecopenia) (neurotoxicty and FBC especially when course >10 days), peripheral neuropathy, infection resolution, CRP, WCC, LFT
C- take with food (except metronidazole liquid is best absorbed in empty stomach), may cause dizziness and confussion- avoid driving if effected, stop taking if you notice any numbness or tingling in extremities, can cause weird sensations/taste in mouth (furry, glossitis, metallic taste)
metronidazole- avoid alcohol during and for 24h post treatment (disulfuram reaction)- will cause NV flushing headache and palpitations
CAL- 2, 5 (metro only), D
Clindamycin
C- lincosamide ABx- bacteriostatic inhibits 50S ribosome and therefore protein synthesis
I- alternative for patients with penicillin/cephalosporin allergy for endocarditis prophylaxis, aspiration pneumonia, dental skin soft tissue and bone infections, toxoplasma encephalitis bacterial vaginosis Anaerobic infections Treatment of PCP Malaria Acne
D
Oral- 150-450mg q6-8h
IV- 600-2700mg daily in 2-4 doses (usually 450-900mg q8h) max IV 4.8g daily
M- allergic reactions and SJS, infection resolution WCC CRP, LFTs (hepatotoxic at high doses), FBC (blood dyscrasias)
C- take with full glass of water, stop taking immediately and see dr if you get diarrhoea, check with dr/pharmacist before taking antidiarrhoeal medication, AE-DNV abdo pain/cramps, dissolve capsules in water and mix with juice/food for children
Murpirocin
C- antibacterial (other)- inhibits bacterial protein synthesis, active against gram +ve aerobes and some gram -ve aerobes
I- mild impetigo (ointment), small infected skin lesions (cream), reduction of nasal carraig of staph (nasal ointment)
D
Nasal- apply (match head size amount) to nostrils bd-tds for 5-7 days (do not use >10 days)
Skin- apply tds for up to 10 days
M- infection resolution (nasal swabs), allergy, localised irritation
C- avoid contact with eyes and mouth, children with impetigo should be excluded until treatment has started and exposed sores are covered with water tight dressing, hand washing and good hygeine is essential. Nasal- squeeze nostrils together after application to spread ointment, you should taste murpuricin at back of throat if applied properly
Rifampacin
C- rifamycin: inhibits bacterial RNA polymerase
I- TB and MRSA in combination with other drugs, leprosy, mycobacterial infections, serious or prosthesis associated infections in combination with other anti-staph agents, prevention of meningococcal or H influenzae type B infection post exposure
(resistance develops rapidly if used as sole agent)
D- 10mg/kg (max 600mg) once daily. Up to 1200mg as been used in staph infections
M- LFTs (hepatotoxicity), renal function (SrCr), FBC (thrombocytopenia), allergy, resolution of infection, WCC, CRP
C- take on empty stomach for best absorption, AE- NV cramping headache myalgia drowsiness, staining of urine sweat faeces and tears orange -red (contact lenses will be permenantly stained), tell dr if you loose appetite NV tiredness jaundice dark urine or pale faeces, multiple DDI- talk to dr/pharm before starting anything, reduced efficacy of OCP- only take active pills during course and for 7 days post and use barrier method, see dr for severe persistent diarrhoea (C diff), see dr immediately for rash or swollen glands, take regularly rather than stopping and starting due to risk of allergy, finish whole course
CAL-3b, 5, D
Trimethoprim
C- ABx (other), bacteriostatic inhibits folate synthesis which is essential for bacterial growth
I- uncomplicated UTI, epididymo-orchitis (urinary source), prostatitis (acute or chronic), mild to moderate PCP with dapasone
D- 300mg at night. UTI prophylaxis 150mg at night
M- Sr K (hyperkalaemia- high risk with high doses and renal impairment), FBC (may worsen megaloblastic anaemia), serum folate, renal function (avoid <15mL/min), AE- fever, itch,NV
C- take at night after emptying bladder to retain high urine concentrations whilst sleeping, take irrespective of food, can cause fever itch NV, finish whole course
CAL- 11
Trimethoprim and Sulfamethoxazole
C- ABx (other), bacteriostatic inhibits folate synthesis which is essential for bacterial growth
I- Treatment and prophylaxis for PCP, melioidosis, shigellosis, prevention of cerebral toxoplasmosis in HIV, prevention and treatment of pertussis (where macrolide is unsuitable), community aquired MRSA (eg skin/ soft tissue)
D- 80/40-320/1600mg bd (max 20/100mg/kg/day in divided doses)
M- Sr K (hyperkalaemia- high risk with high doses and renal impairment), FBC (may worsen megaloblastic anaemia), serum folate, renal function (CI <15mL/min), hypersensitivity (SJS, toxic epidermal necrosis)
C- take with food, drink lots of fluid (2-3L), avoid sun exposure or cover up due to increased sensitivity, see dr asap for sore throat, fever, rash, cough, difficulty breathing, joint pain, dark urine, pale stools, take full course
CAL- 8, 11, B, D
Penicillins
C- Penicllin ABx bactericidal- inhibits cell wall sythesis
Amoxicillin
I-CAP, otitis media, sinusitis, gonococcal, epidiymo-orchitis, acute prostatitis, acute pyelonephritis, UTI, endocarditis prophylaxis, H pylori in combination with clarithromycin and PPI
D-oral 250-500mg q8h or 1g bd (max 1g tds). Take irrespective of food
IV 1g q6h max 12g/day.
Flucloxacillin/ dicloxacillin
I-Staphylococcal skin infections, osteomylitis, septic arthritis, mastitis, cellulitis, impetigo, endocarditis, septicaemia, staphylococcal pneumonia
D- oral 250-500mg q6h. max 4g daily. Take on empty stomach. IV (fluclox only)- 1-2g q6h. max 12g daily
Phenoxymethylpenicillin (PenV)
I- S pyogenes tonsillitis pharygitis or skin infections, prevention of rheumatic fever, mod-severe gingivitis, scarlet fever
D- 250-500mg q6h max 3g daily. take irrespective of food
M- infection resolution (CRP ana WCC), FBC, renal function (SrCr, eGFR, CrCl), hepatic function (cholestatic hepatitis is most common with fluclox++ and diclox)
Amoxicillin- allergy (rash is more common in infectious mononucleosis, ALL, CLL and HIV),
C- take full course, take irrespective of food (exept di/fluclox label 3b- empty stomach), signs of allergy, signs of c diff, see dr if not resolved by end of course
CAL- fluclox and phenoxy- 3b? (but AMH says absorption is not really effected by food)
Quinolones
C- Quinolone antibiotic, bactericidal- blocks DNA gyrase and topisomerase IV preventing DNA synthesis
Ciprofloxacin
I-Salmonella, Typhoid and paratyphoid, shigellosis, complicated UTI, bone/joint infections, Epididymo-orchitis, prevention of meningococcal, P aeruginosa infections (eg CF), Prostatitis, Febrile neutropenia, Keratitis or severe bacterial conjuctivitis (ocular drops), chronic suppurative otitis media
D-Oral 250-500mg bd Max 1.5g daily. IV 200-400mg q8-12h max 1.2g daily
Moxfloxacin
I-CAP with penicillin allergy, acute bacterial sinusitis/COPD exacerbation/severe complicated skin/soft tissue infection where other therapy failed or CI, severe mixed aerobe and anearobic infections, multidrug resistant TB
D-IV/oral 400mg daily
Norfloxacin
I-Uncomplicated UTI, Shigellosis, Travellers diarrhoea, Campylobacter, Prostatitis (acute and chronic), Prophylaxis in cirrhotic patients with GI haemorrhage
D-oral 400mg daily-bd (max daily dose 800mg- can be given 800mg stat for TD)
M- Neurological (irreversible peripheral neuropathy, seizures, avoid in myasthinia gravis), tendonopathy, AE- rash, itch, VDN, abdo pain, dyspepsia, renal function (dose reduction required), ECG prolong QT (moxiflox, rare with cipro), infection resolution (WCC, CRP), moxiflox- LFTs (can cause fulminant hepatitis)
C- take 1h before food or 2h after food for best absorption (cipro and norflox, moxiflox can be taken with food) label 4- avoid dairy/antacids/cations within 2h (moxiflox cross out dairy), increased effects of caffeine (cipro/norflox), increase effects of sun- avoid exposure (cipro/norflox), can cause dizziness/faintness/palpitations- do not drive if effected and avoid alcohol as it may worsen AE, stop taking asap and see dr if tendon pain/inflammation or numbness/tingling in fingers or toes, moxiflox- see dr for yellow skin/ pale stools/ dark urine
CALs
Ciprofloxacin-3b, 4a, 5, 8, 12, D
Moxifloxacin-4a (delete dairy), 12, D
Norfloxacin- 3b, 4a, 8, 12, D
Tetracyclines
C- tetracycline Abx bacteriostatic: binds 30s ribosome preventing protein synthesis
Doxycyline
I-Acne, rosacea, M pneumonia infection, CAP, COPD exacerbation, acute bacterial sinusitis, Chlamydia, PID, Rickettsial infection, melioidosis, sexually aquired epididymo-orchitis, chronic prostatitis, malaria prophylaxis, treatment of P falciparum malaria with quinine, Q fever
D- oral 200mg stat then 100mg daily-bd (max 200mg daily)
M-infection resolution (CRP, WCC), DDIs (avoid with oral retinoids- benign intracranial hypertension), LFTs (hepatotoxic), CI <8yo children- teeth discolouration and bone issues
C- take single dose in morning, take with food or milk to reduce GI upset, swallow whole with large glass of water and remain upright for 1 hour post dose, finish whole course, label 4a- avoid antacids and cations within 2 hours, label 8- sun exposure, malarial counselling- use mosquito repelent and protective clothing, begin 2 days before entering area and continue for 4 weeks after leaving, see dr for febrile illness 12 months after exposure
CAL doxycyline- 4a (delete dairy), 8, 21, A, B, D
Others- Demeclocycline, minocycline, tetracycline
