Antibiotics

Aminoglycosides - When do you measure serum-gent doses? + What are the peak serum conc + trough concs for normal infections + endocarditis?

Amikacin, Gentamicin, Neomycin, Streptomycin + Tobramycin

After 3 or 4 doses, then every 3 days + after a dosage change

- Measure 1hr after dose + just before the next dose

Normal: Peak - 5-10mg/L + Trough <2mg/L

Endocarditis: Peak 3-5mg/L + Trough <1mg/L

Aminoglycosides - What are the dose adjustments for when trough is too high + peak is too high + in renal impairment?

Trough too high = Increase dosing interval

Peak too high = Reduce dose

Rena impairment = Increase dosing interval

Aminoglycoside - MHRA warning + CIs + SEs + IBW or Actual body wt?

MHRA - Ototoxicity + Nephrotoxicity

CI - Myasthenia gravis + avoided in pregnancy

SEs - SJS

IBW for dosing in obese pts

Cephalosporins - Cross-sensitivity + SEs + Pregnancy + breastfeeding?

1^st gen: Cefadroxil, Cefalexin, Cefradine

2^nd gen: Cefuroxime, Cefoitin, Cefaclor

3^rd gen: Cefataxime, Cetazidime, Ceftriaxone, Cefixime

4^th gen: Cefepime

5^th gen: Ceftaroline + Ceftobiprole

Avoid in pts with hypersensitivity to penicillins + other beta-lactams

SEs - Diarrhoea, N+V, abdominal pain

Not known to be harmful in pregnancy + breastfeeding

Chloramphenicol - SEs

Grey-baby syndrome - Avoid systemic Tx in pregnancy + breastfeeding

Hypersensitivity

Bone marrow depression

Clindamycin - SEs + What are the drugs that cause C.diff?

SEs - SJS - discontinue

C.diff - Clindamycin, Co-amox, Cepholasporins, Ciprofloxacin

Glycopeptides - MHRA? + SEs

Dalbavancin, Teicoplanin, Oritavancin + Vancomycin

MHRA - Ototoxicity

Glycopeptides - Vanc SEs + How to dose? When to measure conc + trough conc?

Blood dyscrasias - agranulocytosis, eosinophilia, neutropenia, thrombocytopenia

Hypersensitivity reactions (SJS + anaphylaxis)

Infiusion related SEs - Red man syndrome if rapid bolus admin

Pain + thromboplebitis

Dosed on body wt + then adjust based on serum-vanc concs

Measure on 2nd day of Tx immediately prior to the next dose

Trough = 15-20mg/L

Linezolid - SEs + Interactions?

Peripheral + Optic neuropathy - report numbness, tingling, visual impairment

Risk of myelosuppression (blood dyscrasias) - anaemia, leucopenia, pancytopenia + thrombocytopenia

Interacts with tyramine rich food

Risk of serotonin syndrome

Macrolides - Cautions? + SEs? + interactions

Cautions

-Severe hepatic / renal impairment

-Hypokalaemia

-Pts predisposed to QT interval prolongation

-Myasthenia gravis

SEs - GI disturbances, N+V, taste altered, diarrhoea, ototoxicity, QT prolongation, hepatotoxicity

CYP inhibitor - increases conc of rivaroxaban, warfarin, CCB, statins, theophylline

Metronidazole - Anaerobic antibiotic - SEs? + Counselling

Taste disturbance, N+V (take with food), Diarrhoea

Must not drink alcohol + for 2 days after → disulfiram like SEs = N+V, stomach pains, hot flushes, palpitations

Nitrofurantoin - CrCl? +Pregnancy + MHRA? + urine colour

Avoid in <45ml/min

Avoid only at term (>37wks) - neonatal haemolysis

MHRA - Pulmonary + hepatic events - take with food

Urine yellow or brown

Penicillins - SEs? + True penicillin allergy presentation?

Urticaria = hives

Diarrhoea, N+V, antibiotic-associated colitis, hypersensitivity reactions (rash, hives, pruritus)

Penicillin allergy - anaphylaxis, widespread rash, breathing difficulties, collapse, swelling

Penicillins - MHRA + Interactions?

MHRA - Fluclox + Co-amox = Hepatitis + cholestatic jaundice can occur up to 2m after Tx

Interactions:

-MTX = reduced clearance = MTX toxicity

Warfarin - Alters INR = decreases Vit K production → increases INR

Allopurinol = Increased risk of allergic skin reactions

Quinolones - MHRA warnings?

Ciprofloxacin Levofloxacin Moxifloxacin Ofloxacin

Tendonitis - Common in over 60s, female, renal impairment, Tx with corticosteroids

Neuropsychiatric reactions

Heart valve regurgitations

Aortic valve aneurysm + dissection

Long-lasting SEs on musculoskeletal + nervous system

Only Rxed when other abx are inappropriate

Prolongs QT

Quinolones - Interactions?

Iron, Zinc + Antacids - Take cipro 2hrs before

Avoid diary products + mineral-fortified drinks = reduces exposure to quinolone

NSAIDs - Reduces seizure thresholds

Tetracyclines - SEs? + Which can be taken with milk?

Doxycycline, Demeclocycline, Lymecycline, Minocycline, Oxytetracycline, Tetracycline + Tigecycline

Minocycline - drug induced lupus, skin pigmentation + hepatitis

Avoid in under 12yrs, pregnant / breastfeeding

Cautioned in myasthenia gravis

Benign intracranial hypotension - stop + report headaches + visual disturbances

Photosensitivity

Oesophagitis - Swallow with whole glass of water

Hepatic impairment

Milk - Doxycycline, lymecycline, minocycline

Trimethoprim - SEs? + Interactions? + pregnancy? + long term Tx

SEs - Blood dyscrasia, hyperkalaemia, hyponatraemia + renal impairment

Anrtifolate - teratogenic risk = avoid in 1st trimester

Interactions with MTX + Phenytoin

Long-term Tx - report fever, sore throat, rash ulcers, bruising, bleeding

TB meds?

Rifampicin - discolour bodily fluids red

Isoniazid - peripheral neuropathy = given with pyridoxine (B6)

Ethambutol - visual impairment due to optic neuritis

Hepatotoxic - rifampicin, isoniazid + pyrazinamide

Anti-fungals - General SEs + SEs with Itraconazole, ketoconazole, Voriconazole + amphotericin B?

QT prolongation

Itraconazole - Caution in HFrEF, concetraception during Tx and until the menstrual period following end of Tx

Ketaconazole - Serious hepatotoxicity

Voriconazole - photosensitivity, squamous cell carcinoma, SCARs

Amphotericin B - test dose with 30mins observations → use slower infusion (2hrs), can use diphenhydramine, paracetamol + hydrocortisone before infusion + use same formulation

Isotretinoin - MHRA warnings?

HCPs can prescribe isotretinoin to those under 18-years old without seeking the agreement of a second prescriber

PPP for people with childbearing potential

→ Contraception taken 1m before ® till 1 m after

→ Prescription is valid for 7 days + limited to 30 days supply

Rare erectile dysfunction + decreased libido

Risk of neuropsychiatric reactions – seek medical attention in mood change

Avoid UV light, laser skin treatment, dermabrasion + epilation – during Tx + a slight period after Tx

Anti-Malarial Prophy - Which one in pregnancy? + Which one in pts with seizures? + Longest anti-malarial?

Pregnancy - chloroquine but mefloquine in 2nd or 3rd trimester in high-risk areas only

Epilepsy - doxycycline or atorvaquone with proguanil

Chloroquine longest

Anti-malarial MHRA warnings?

Mefloquine - Neuropsychiatric reactions

Chloroquine - Neuropsychiatric reactions + increased CVD events when given with macrolides

Doxycyline - Phototoxicity