Chapter 5: Infections Flashcards
What is antibiotic stewardship?
Organisational or healthcare system wide approach to promoting and monitoring judicious use of antimicrobials to persevere their future effectiveness.
What is the difference between antibiotic and antimicrobial resistance?
Antibiotics resistance: resistance to ABX that occurs in common bacteria that cause infections.
Antimicrobial resistance: broaden term including resistance to drugs to treat infections caused by other microbes including parasites (e.g. malaria), viruses (e.g. HIV) and fungi (eg candida), Protozoa
What is antimicrobial resistance?
The ability of microorganisms to become increasingly resistance to a antimicrobial agent to which they were previous susceptible.
AMR is a consequence of genetic mutation and natural selection.
Such mutation is then passed on conferring resistance.
AMR cannot be eradicated but managed to limit their impact on health
What are the main causes of AMR?
Availability of antibacterials without a Rx in some countries.
Patient demand for antibacterials for inappropriate infection.
Failure of patients to complete their prescribed course of antibacterials.
Overuse and misuse of antibacterials in humans, animals and agriculture.
How can pharmacist help with AMR?
- Improving infection prevention control.
- Making sure the right antibacterial is given for the right clinical indication, at the right dose, right time, right direction, right route and duration.
- when there is clinical uncertainty about a condition, back up or delayed prescribing can be used to offer an alternative to immediate prescribing.
- by checking that antibiotics and other antimicrobials are prescribed when needed, comply with local guidance and query if not so.
- don’t prescribe for self limiting conditions.
- give patient clear advice including the duration, frequency, dose, potential SEs and return unused antibacterials to the pharmacy.
- by providing information on self limiting infections, use PILs to explain duration and how to treat the symptoms.
List self limiting conditions?
Common cold Acute otitis media Acute cough Acute bronchitis Acute sore throat Acute pharyngitis Acute tonsillitis Acute rhionsinuitis
What should be considered before treating antibiotics?
- Avoid blind therapy
- Take samples for culture and sensitivity testing
- Use narrow spectrum abx when possible
- Avoid prolonged use of abx: can lead to SEs, encourage resistance and are costly.
- Limit telephone prescribing to exceptional cases
- always check for allergies
- for immunocompromised patient: start treatment immediately.
What is superinfection?
- An infection caused by an infection.
- Broad spec antibacterials are more likely to cause side effect, eg.g Abx associated colitis, fungal infections and vaginitis, pruritus ani (itchy bum)
When should a Doctor notify the proper officer of suspected cases of notifiable diseases?
- Complete and send notification form and send within 3 days
- Verbal notification (phone, letter, e-mail, secure fax): within 24 hours for urgent cases
List examples of notifiable diseases?
Food poisoning Infectious bloody diarrhoea TB Plague Meningococcal septicaemia Scarlet fever Smallpox Whooping cough (pertussis) Meningitis Acute encephalitis
What is the difference between sepsis and septicaemia?
Sepsis: infection of the whole body
Septicaemia: blood infection
How soon should treatment for sepsis be started and monitored?
- ASAP, ideally within 1 hour
- monitor every 30 mins
What are the 6 main signs and symptoms of sepsis?
- Higher RR (normal: 12-20 breaths per min)
- Higher or low HR (normal: 60-100 bpm)
- Lower O2 stats (normal: 95-100%)
- Systolic BP < or = to 90mmHg if age 12 and above
- Higher or lower Temperature (normal 36.1-37.2 degrees)
- Reduced Consciousness/confusion
What are the additional signs and symptoms of sepsis?
- Lactate levels 2mmol/L or above
- Non blanching, mottled/ashen or cyanotic skin rash (like meningitis)
- Not passed urine/dehydration
- Infection, fever, cold and shivers
What additional signs and symptoms are seen in children and babies in sepsis?
Feel abnormally cold to touch Has a fit or convulsion No wet nappies for 12 hours or more No interest in feeding Soft spot on baby’s head is bulging Weak whining or continuous crying
What is sepsis 6?
It’s the recommendations for the early management of sepsis.
- 3 tests:
1. blood cultures immediately before treatment
2. Blood sample to assess severity
3. Monitor urine output to assess kidney damage (AKI)
3 Treatments:
- IV broad spec abx (within 1 hour of admission)
- IV fluids (within 1 hour of admission)
- O2 to counteract lactate if needed to keep stats over 94%
(Give vasopressors and inotropes e.g. DA and adrenaline to improve BP if needed)
What future tests can be conducted in sepsis?
FBC: WBC, C reactive protein, lactate Clotting factors, D- dimer (linked to blood clots) Chest x-ray Urine analysis CT scan (meningitis)
What are the risk factors of sepsis?
Very young and old
Immunocompromised patients (HIV, cancer, patients on steroids and diabetics, and transplant patients)
Pregnancy
IV drug misusers
What is given for rheumatic fever prevention?
Pen(V)
Or Sulfadiazine
What is given for pertussis prophylaxis?
CLARITHYROMYCIN ‘ACE’
What is given for pneumococcal infection in aslpenia or in patients with sickle cell disease prophylaxis?
Pen v adult: 250mg BD
If pen allergic: erythromycin
What is given for ANIMAL and human bites prophylaxis?
Co-amoxiclav alone (375-625mg TDS) up to 5-7 days
Pen allergic: (doxycycline 100mg BD+ metronidazole 400mg TDS)
What is given for community and hospital acquired septicaemia?
A broad spec antipseudomonal penicillin:
1. Piperacillin/tazobactam
Or broad spec cephalosporin e.g. cefuroxime
(Hospital alternative: meropenem or cilstatin and imipenem)
MRSA suspected: add vancomycin or teicoplanin
If anaerobic suspected: add metronidazole to broad spec cephalosporin.
What is given for meningococcal septicaemia ?
Single dose of IV Pen G. Give before urgent admission to hospital.
Pen allergy alternative: IV Cefuotaxime
If hypersensitivity to pen and cephalosporins: IV Chloramphenicol
What is given for initial blind treatment of endocarditis (HEART)?
Amoxicillin or ampicillin (consider adding low dose gentamicin)
-If MRSA or severe sepsis suspected give vancomycin + low dose gentamicin
What is given for endocarditis caused by staphlococci (HEART)?
Flucloxacillin
If pen allergic or MRSA suspected give vancomycin and rifampicin
4 week treatment
What is the of meningitis caused meningococci?
-If meningococcal suspected: Pen G should be given before hospital transfer if possible.
-Pen allergy: cefotaxime
7 days treatment
- If history of hypersensitivity to pen and cephalosporins: Chloramphenicol
- 7 days treatment
What is given for meningitis caused by pneumococci?
Cefotaxime (or ceftiaxone)
Consider adjunct treatment with dexamethasone, starting within 12 hours after starting antibacterial.
Duration of 14 days treatment
What organisms causes otitis externa?
Pseudomonas aeruginosa or staphyl aureus
What is given for otitis externa? (OTC and Rx)
1st line: localised heat, and analgesics
2nd line: acetic acid 2% EarCalm (7 days, 1 Spray TDS)
If spreading cellulitis or disease extended beyond ear canal:
- Flucloxacillin (250-500mg qds) 7 days
- If pen allergic: ACE
-If pseudonomas suspected:
Ciprofloxacin or an aminoglycoside
What is given for acute otitis media?
Regular paracetamol/ibuprofen
If not improvement after 72 hours or if systemically very unwell or high risk of complications:
Amoxicillin 500mg TDS 5-7 days
Alternative co-amoxiclav
If pen allergic give Macrolides (Clarithromycin or Erythromycin )
What is given for gastroenteritis?
Self limiting, therefore no treatment neccesary
What is Clostridium difficult infection and which antibiotic has the greater risk?
An infection caused by colonisation of the colon with C.Difficile and production of toxin.
-Ampicillin, amoxicillin, co-amoxiclav, 2nd and 3rd gen cephalosporin, clindamycin and quiniolone all have GREATER RISK
What is given for first episode of mild to moderate C diff infection?
Oral metronidazole 400mg TDS 10-14 days
What is given for 2nd/subsequent episode OR for severe infection of C Diff?
Oral vancomycin 125mg QDS for 10-14 days
Alternative is fidaxomicin
What is given for H pylori infection (FIRST LINE)?
PPI
+ clarithromycin 500mg BD (strength halved if given with metronidazole)
+ amoxicillin 1000mg BD OR metronidazole 400mg BD
for 7 days
What is given for H pylori infection in Pen allergy or used clarithromycin already within year?
Pen allergy:
PPI
+clarithromycin 250mg BD
+metronidazole 400mg BD
Clarithromycin used already: PPI \+Bismuth subsalicylate \+Metronidazole 400mg BD \+Tetracycline 500mg QDS
What is given for infectious diarrhoea (campylobacter enteritis)?
A.K.A food poisoning
Frequently self limiting
However, if systemically unwell(severe infection) or immunocompromised, give:
ACE
Alternative: ciprofloxacin
What is given in salmonella?
ONLY treat if patient is systemically unwell (severe infection), immunocompromised patient, or <6months old
Give ciprofloxacin
What is given in bacterial vaginosis?
Oral metronidazole 400-500mg BD for 5-7days
OR single 2g dose
Alternative: topical metronidazole 5days or topical clindamycin 7days
What is given for uncomplicated genital chlamydia and non-specific genital infection?
Azithromycin 1g SINGLE dose
Or doxycycline 100mg BD for 7 days
What is given for gonorrhoea?
Azithromycin + ceftriaxone IM (stat dose)
What is given for osteomyelitis?
Seek specialist advice if chronic infection or prostheses present.
Give flucloxacillin - 6 week treatment
Consider adding fusidic acid or rifampicin for initial 2 was
If pen allergic give clindamycin
What causes sinusitis (acute)?
Triggered by viral infection but may become complicated by bacterial infection caused by:
- Streptococcus pneumoniae,
- H. Influenzae
- Moraxella catharrhalis
What is given for sinusitis?
Give paracetamol or ibuprofen for pain
ONLY treat patients antibiotics who are systemically unwell or high risk of complications. Give co-amoxiclav 625mg TDS for 5 days
Give PenV 500mg QDS for 5days (non-life threatening symptoms)
In pen allergy give doxycycline, clarithromycin or erythromycin
What do you do if sinusitis symptoms duration is 10 days or less?
NOTHING (Don’t give antibiotic)
What do you do if sinusitis symptoms duration is longer than 10 days with no improvement?
Give NO antibiotic or BACK-UP antibiotic
What is given for the exacerbation of COPD?
Amoxicillin 500mg TDS, doxycycline(200mg stat, then 100mg OD) or clarithromycin (500mg bd).
5 days treatment
What organisms cause COPD exacerbations?
- Streptococcus pneumoniae,
- H. Influenzae
- Moraxella catharrhalis
What is the difference between CURB-65 and CRB-65?
It’s a 1 point system
Curb-65 (hospital acquired) pneumonia that develops 48 hours after hospital admission.
C= confusion U= urea > 7mmol/l (HOSPITAL ONLY) R= RR 30breaths per min or more B= sBP is < 90 or dBP is 60 or less AGE= 65 or more
CRB-65 is community acquired pneumonia
What do the severity scores for CAP OR HAP indicate?
0-1: low severity
2: moderate severity
3-5: high severity
what is the treatment for CAP?
-Low severity: Amoxicillin 500mg TDS or doxycycline or clarithromycin 500mg (‘ACE’)bd for 7 days.
-moderate severity: Amoxicillin 500mg -1g TDS + clarithromycin 500mg bd (‘ACE’)
If oral not possible give IV versions
ALTERNATIVE: oral doxycycline ALONE (7-10 DAYS)
-high severity: Pen G 1.2g TDS + clarithromycin 500mg BD (7-10 days)’ACE’
Or Pen G + doxycycline
If life threatening infection, or gram -ve infection suspected, or co-morbidities present, or if living in long-term nursing home, give:
Co-amoxiclav 1.25g TDS IV + clarithromycin 500mg IV bd.
Alternatively give:
Cefuroxime + clarithromycin or ‘ACE’
What is the treatment of HAP?
Early onset less than 5 days after admission: give co-amoxiclav or cefuroxime. 7 days treatment.
Late onset more than 5 days after admission: give tazocin or broad spec cephalosporin such as ceftazidime OR ciprofloxacin. 7 days treatment.
What do we give for small areas of impetigo on the skin?
Topical fusidic acid (7-10 days)
If MRSA suspected: topical mupirocin 7-10 days
What is given for widespread impetigo on the skin?
Flucloxacillin
If streptococci suspected: ADD Pen V
If pen allergic: give ACE
7 day treatment
What is given for cellulitis?
Flucloxacillin (high dose) 500mg QDS
If streptococcal suspected: replace with Pen V or Pen G
If pen allergic: ACE or clindamycin, vancomycin or teicoplanin.
What is organism causes mastitis? What treatment is given for mastitis?
Straphylcococcus aureus
Treat if severe, if systemically unwell, if symptoms do not improve after 12-24 hours of effective milk removal.
Flucloxacillin 10-14 days
If pen allergic: erythromycin 10-14 days
What is given for acute pyelonephritis?
inital Injection of broad spec cephalosporin cefuroxime (250mg bd) OR ciprofloxacin (500mg bd) if severely ill.
Gentamicin can also be used.
Duration 10-14 days
List some aminoglycosides
Amikacin Gentamicin Neomycin Streptomycin Tobramycin
What is the therapeutic range for multiple daily dosing for gentamicin and amikacin?
- Gentamicin:
peak conc: 5-10mg/L
Trough (pre dose conc) <2mg/L - Amikacin:
Peak conc <30mg/L
TROUGH conc <10mg/L
Once daily dosing for amikacin:
Trough< 5mg/L
What is the therapeutic ranges for gentamicin for endocarditis treatment?
Peak conc: 3-5mg/L
Trough: <1mg/L
Which group of people must have their serum conc levels measured when taking parenteral aminoglycosides?
Elderly
Obesity
Cystic fibrosis
If high doses are being given
In patients with normal renal function, when do you measure aminoglycoside conc for multiple daily regimen?
Measure after 3-4 doses have been given
Take blood sample 1 hour after the dose= peak conc
Trough: take blood Sample just before the next dose
Route of admin: IM OR IV
What do you do if the peak conc (post dose) or trough (pre dose ) is higher than normal?
Peak conc: reduce the dose
Trough: increase the dose=increase dosing interval
What are the monitoring requirements other than serum concs for aminoglycosides?
Renal function: baseline and during treatment
Auditory and vestibular function: during treatment
What is the route of elimination of aminoglycosides?
And what are the major side effects?
Renally excreted
Accumulation occurs during renal impairment increasing risk of otoxicity and nephrotoxicity
what conditions should once daily dosing for aminoglycosides be avoided in?
- Patients Endocarditis due to gram +ve bacteria
- patients with burns of more than 20% of the total BSA
- patients with CrCL <20ml/min
- patients with HÁČEK endocarditis
Insufficient evidence to recommend once daily dosing in pregnancy.
What other ototoxic and nephrotoxic drugs should be avoided with aminoglycosides?
Ototoxic drugs:
Loop diuretics
Vancomycin
cisplatin
Nephrotoxic: Cisplatin Ciclosporin Tacrolimus Vancomycin
What patient advice should be given regarding aminoglycosides?
- Report signs and symptoms of hearing issues (ototoxicity)
- Ensure patient is drinking adequate fluids to prevent dehydration before starting treatment.
What is the CI of aminoglycosides?
Myasthenia gravis: May impairment neuromuscular transmission.
Why is imipenem given with cilastatin?
Imipenem is partially inactivated by the kidneys by enzymatic activity.
Therefore cilastatin is an enzyme inhibitor that blocks renal metabolism.
List examples of 1st gen cephalosporins?
Cefalexin
Cefradine
Cefradroxil
List examples of 2nd gen cephalosporins?
Cefaclor
Cefuroxime
List examples of 3rd gen cephalosporins?
Cefixime
Ceftriaxone
Ceftazidime
Cefotaxime
List examples of 5th gen cephalosporins?
Ceftraroline fosamil
What is the mechanism of action for cephalosporin?
Prevents cell wall synthesis by binding to enzymes called penicilin binding proteins.
Bactericidal with both gram +ve and -ve activity
What % of penicillin sensitive patients are allergic to cephalosporins?
0.5-6.5%
If cephalosporins are essential and patients have a hypersensitivity reaction what cephalosporins alternatives are given?
Cefuroxime
Cefixime
Cefotaxime
Ceftazidime
What are common SEs of cephalosporins?
Abx associated colitis (rare but more common in 2nd and 3rd gen)
What is the mechanism of action of trimethoprim?
What is it effective against?
Binds and reversibly inhibits bacterial dihydrofolate reductase and blocks the production of tetrahydrofolate.
Wide range of group gram +ve and aerobic gran -ve organisms
What are the CI and cautions of trimethoprim and co-trimoxazole?
Blood dyscrasias
Pregnancy (especially in the 1st trimester)
What is the MHRA/CHM warning for co-trimoxazole
Steven johnson’s syndrome. Symptoms: Flu like symptoms Red- purple rash Hives Shedding of skin
What is in co-trimoxazole?
Trimethoprim + sulfamethoxazole
When is co-trimoxazole the drug of choice?
Prophylaxis and treatment of pneumocystis jirovecii
List examples of glycopeptides?
Vancomycin
Teicoplanin
Telavancin
Which type of organism are glycopeptides active against?
Glycopeptides have bactericidal activity against gram +ve bacteria
What are glycopeptides used to treat against?
Meticillin-resistant staphylococcus aureus (MRSA) infections
What is the therapeutic range for vancomycin?
Trough should be between 10-20mg/L
15-20mg/L is for endocarditis, or less sensitive strains of MRSA
What are the monitoring requirements for vancomycin?
- Serum vancomycin monitoring on second day of treatment (dosing is based on body weight)
- Periodic renal, hepatic function, urinalysis, blood counts
- Auditory function (during and after treatment in elderly)
What is the route of elimination for vancomycin?
Renally excreted and 70-90% excreted unchanged in urine
How many times a day should vancomycin and teicoplanin be given and why?
Vancomycin BD
Teicoplanin OD due to longer duration of action
What are the SEs and warning signs that should be immediately reported when using vancomycin?
- Ototoxicity: Hearing loss, vertigo, dizziness, tinnitus (DISCONTINE)
- Red man syndrome: Flushing of upper body
- Blood dyscrasias (neutropenia, thrombocytopenia, sore throat etc.)
- Phlebitis (inflammation on site of IV admin, can cause clots)
- Nephrotoxicity (elevated serum creative concs) more common in vanco than teicoplanin
- Stevens Johnson syndrome/toxic epidermal necrolysis, pruritus
What happens if vancomycin is administered too quickly?
Hypotension and anaphylactic reactions can occur
Also red man syndrome can occur if given too quickly or too much.
Rate should not exceed 10mg/min
What drugs interact with vancomycin?
Increased risk of nephrotoxicity and ototoxicity with aminoglycosides, ciclosporin and furosemide
What drug is a lincosamide?
Clindamycin
What is the major SE of clindamycin that requires discontinuing?
Antibiotic-associated colitis. Patient should DISCONTINUE immediately and contact a doctor if diarrhoea occurs
And also if C-diff infection is suspected or confirmed
Which type of organism is clindamycin active against?
Gram +ve bacteria including streptococci and penicillin-resistant staphylococcus
Which part of the body is clindamycin well concentrated in?
Well concentrated in the bones and therefore commonly used in staphylococcal joint and bone infections
What are the monitoring requirements for clindamycin?
Monitor renal and liver function if treatment exceeds 10 days
In infants and neonates monitor this regardless of duration of treatment
List examples of macrolides? Include the frequency of dose
ACE!
Azithromycin OD
Clarithromycin BD
Erythromycin QDS
What are the indications for macrolides?
Campylobacter enteritis
Respiratory-tract infections (inc. pneumonia, whooping cough/pertussis (1st line), legionella)
Which of the macrolides is given for chlamydia trachomatis genital infection and what are the legal requirements for selling OTC?
Azithromycin - 1 tablet pack size, 1g strength, sell only to patients >16yrs old who have CONFIRMED asymptomatic chlamydia
What are the cautions of macrolides?
- Electrolyte disturbances (predisposes to QT interval prolongation)
- May aggravate myasthenia gravis
What are the common SEs oil macrolides?
Decreased appetite Arthralgia GI SEs (more common in erythromycin) Hepatotoxicity Skin reactions (rash)
Which of the macrolides should be avoided in pregnancy?
Azithromycin (avoid but use only if no other alternative available)
Clarithromycin (avoid particularly in 1st trimester)
What is the advisory label for azithromycin and erythromycin tablets?
Do NOT take indigestion remedies 2 hours before or after
Which type of organism is metronidazole active against?
Antimicrobial drug active against anaerobic bacteria and Protozoa
What are the indications for metronidazole?
- Topically used to treat rosacea
- Used to treat c-diff infection , H. pylori infection, bacterial vaginosis
What is the advisory label for metronidazole?
Take with or just after food
Describe the reaction that can occur if metronidazole is taken with alcohol and how long to avoid use for.
Disulfiram-like reaction: flushing, palpitations, N+V
(also alcohol-containing mouthwash)
Avoid 2 days after completing metronidazole course
What drug is an oxazolidinone?
Linezolid
Which type of organism is linezolid active against?
Gram +ve bacteria including MRSA and vancomycin-resistant enterococci
What are the CSM advice concerning linezolid?
- Severe optic neuropathy (visual disturbance) can occur if used for >28 days
- Blood disorders which include thrombocytopenia, anaemia, leukopenia.
-close monitoring is recommended in patients who:
Receive treatment for more than 10-14 days
Have pre-existing myelosuppression.
Are receiving drugs that may have adverse effects on haemoglobin, blood counts or platelet function.
Have severe renal impairment.
What are the monitoring requirements for linezolid?
-Monitor full blood counts (platelet counts) WEEKLY
What should be avoided when taking linezolid and explain why?
Avoid large amounts of tyramine rich foods, other MAOIs (avoid during and 14 days after stopping the MAOI) and certain medications (decongestants).
Because linezolid is is a reversible non-selective MAOI.
What are the CI and cautions of linezolid?
Acute confusional states, bipolar, depression, elderly, history of seizures and uncontrolled HTN.
What are the 5 common groups of penicillins?
- Beta-lactamase sensitive: Pen G and Pen V
- Broad spec (but inactivated by beta lactamases): amoxicillin, ampicillin.
- Penicillinase resistant: Flucloxacillin
- Anti pseudonomal: piperacillin/ticarcillin
- Mecilliam type: pivecillinam.
What is the mechanism of action of penicillins?
Bactericidal, by interfering with bacterial cell wall synthesis.
Penicillin diffuse well into body tissues and fluid but poorly penetrates into cerebrospinal fluid EXCEPT WHEN MENINGES ARE INFLAMED (e.g. PenG given for meningitis)
What organisms does Pen G and Pen V target?
Pen G:
Streptococcal (including pneumococcal), gonococcal, and meningococcal infections
Pen V:
Streptococcal, pneumonococcal infections.
DO NOT USE FOR MENINGOCOCCAL OR GONOCOCCAL INFECTIONS.
What route of administration can Pen G be given and why?
IV only
Due to the inactivation of gastric acids and absorption from the GI tract is low
What route of administration can Pen V be given?
Oral only.
More stable in gastric acid compared to Pen G
What is the common frequency that Pen V is given?
What is the advisory label?
Usually QDS.
Take on an empty stomach- 1 hour before food or 2 hours after food.
What is Flucloxacillin active against
Penicillins resistant staphylococci
What route of administration can Flucloxacillin be given and why?
Oral and IV
Active stable and well absorbed by the gut
What are the SEs of Flucloxacillin?
GI disorders,
Hepatic disorders:
Cholestatic jaundice and hepatitis may occur rarely, up to 2 months after treatment has stopped.
Admin for more than 2 weeks and increasing age are risk factors.
What should healthcare professionals be reminded of when thinking about giving Flucloxacillin?
Flucloxacillin should not be given in patients with a history of hepatic dysfunction associated with Flucloxacillin.
Use with caution in patient with hepatic impairment.
What is common frequency of administration of Flucloxacillin?
And what is the advisory label?
Usually QDS
Give on empty stomach- 1 hour before food or 2 hours after food
What is broad spec penicillins active and inactive against?
Active against certain gram +ve and -ve, streptococcus infection and H.inflenzae.
Inactivated by penicillinase including those produced by staphylococcus aureus and E.coli (gram -ve, about 60% of strains) and 20% of strains for H.inflenzae.
What is the route of admin of ampicillin and amoxicillin
its advisory label?
Ampicillin:
Oral, but less than 50% of the dose is absorbed by the gut.
Usually qds
Absorption is further decreased by the presence of food.
Give on empty stomach- 1 hour before food and 2 hour after food
Amoxicillin:
Oral and IV
Can be given with or without food. Absorption unaffected.
Usually TDS
Which of the penicillins may cause maculopapular rash and is it anything to be worries about?
Common with amoxicillin and ampicillin BUT not a true allergy.
They always occur in patients with glandular fever therefore DO NOT GIVE BLIND TREATMENT for sore throat
The risk of this happening is increased in patients with acute or chronic leukaemia or cytomegalovirus infection.
What is co-amoxiclav?
Broad spec
TDS
Not inactivated by beta lactamase due to the clauvanic acid (beta lactamase inhibitor).
What is co-amoxiclav active against?
Activate against beta lactamase producing bacteria that are resistant to amoxicillin.
These include resistant strains of staph aureus, E.coli and H.inflenzae
What is co-fluamipicil and what type is it?
Ampicillin and Flucloxacillin.
Broad spec
What is Tazocin?
Antipseudomonal penicillin
Piperacillin (ureido penicillin) and Tazobactam (beta-lactamase inhibitior)
What is Timentin?
Antipseudomomal penicillin
Ticarcilin (carboxypenicllin)and clauvanic acid (beta-lactamse inhibitor)
What are antipseudomonal penicillins (tazocin+timentin) active against?
Active against gram +ve, gram -ve (P.aeruginosa) and anaerobes.
NOT ACTIVE AGAINST MRSA.
What is the name of a mecillinam-type penicillin and what is it hydrolysed to?
Pivmecillinam hydrochloride
It is hydrolysed to mecillinam, which is the active drug
What is Pivmecillinam hydrochloride active and not active against?
Active against many gram -ve bacteria inc. E. coli, klebsiella, salmonella, Enterobacter
NOT active against P.aeruginosa, and enterocci
What are the major cautions when taking co-amoxiclav?
Cholestatic jaundice can occur during or shortly after administration. (More common in men and age >65)
-MAX 14 day treatment ONLY
It is not usually fatal though, its usually self limiting. Make sure duration of treatment doesn’t exceed 14 days
What percentage of those exposed to penicillins experience allergic reactions?
Allergic reactions occur in 1-10% of exposed patients
Whic type of patients are at a higher risk of anaphylactic reactions with penicillins?
Patients with higher risk of atopic allergy are at a higher risk. This includes: -hayfever -asthma -eczema
Which individuals should NOT receive penicillin?
Patients with history of anaphylaxis, urticaria, or rash that occurs immediately after penicillin administration are at risk of immediate hypersensitivity to penicillins
Which individuals are not likely to be allergic to penicillin?
Patients with history of a minor rash which is non-confluent (not merging), non-pruritic (not itchy) and is confined to small area of body
OR
Rash which occurs after 72hrs after penicillin administration
ARE NOT LIKELY TO BE ALLERGIC
Which route of injection is Pen G not recommended?
Intrathecal injection
List examples of quinolones
Ciprofloxacin Levofloxacin Moxifloxcin Norfloxacin Ofloxacin
What is the mechanism of action of quinolones?
Inhibit topoisomerases (enzymes necessary for bacterial DNA replication)
Which of the quinolones should NOT be taken with milk, indigestion remedies, iron or zinc-containing meds 2 hrs before and after?
Ciprofloxacin
Norfloxacin
What is the main advisory label for all quinolones?
Should NOT be taken with indigestion remedies, iron or zinc containing-meds 2 hrs before and after administration?
What are the patient and carer advice for quinolones?
- Can cause drowsiness therefore may impair performance of skilled tasks (driving)
- Avoid exposure to excessive sunlight
- Avoid use of NSAIDs (can induce convulsions)
What is the CSM advice for quinolones?
- Can induce convulsions in patients with or without history of convulsions
- NSAIDs, SSRIs, theophylline and tramadol can increase convulsions when taken with quinolones
- Reports of tendon rupture can occur within 48 hours of starting treatment or after several months of stopping. DISCONTINUE if tendontis suspected
- Risk of tendon damage increases when using corticosteriods
- Patients 60 yrs old or more tendon damage prone
- Small increased risk of aortic aneurysm and dissection. Elderly at higher risk. Seek medical attention if sudden and severe abdominal chest or back pain develops
What are the cautions when using quinolones?
Use with caution in patients with:
- History of epilepsy/predisposition to seizures
- G6PD deficiency
- Myasthenia gravis
- Children/adolescents (risk of arthropathy in weight bearing joints)
- Prolonged QT interval
- Diabetes (may affect BG)
- Exposure to excessive sunlight
What are the SEs of quinolones?
GI SEs (N+V, diarrhoea, dyspepsia)
Headaches
Dizziness
Skin reactions
Discontinue if psychiatric, neurological or hypersensitivity (severe rash) reaction occurs
What are the 2 stages of TB treatment including the drugs and duration of treatment?
Initial phase: R I P E (4 drugs, 2 months)
Rifampicin, isoniazid, pyrazinamide, ethambutol
Continuation phase: R I (2 drugs, 4 months)
Rifampicin, isoniazid
List the antituberculosis drugs used in TB
Rifampicin
Isoniazid
Pyrazinamide
Ethambutol
Which antibiotic is used if resistant to isoniazid or not tolerated?
Streptomycin
Which vitamin is given with isoniazid and why?
Vitamin B6, pyridoxine to prevent isoniazid-induced peripheral neuropathy
What are the main SEs of rifampicin?
- Hepatic disorders (N+V, malaise, jaundice) DISCONTINUE and seek medical attention if signs and symptoms occur
- Discolours urine and bodily secretions orange/red (urine, sweat, sputum, tears, contact lenses)
- Influenza-like symptoms (chills, fever, dizziness, bone pain), respiratory symptoms (SOB), haemolytic anaemia, thrombocytopenic purpura and acute renal failure
Is rifampicin an enzyme inducer or inhibitor?
When is it taken?
Potent enzyme inducer
30-60 mins before food
What are the major SEs of isoniazid?
-Peripheral neuropathy
Patients with: diabetes, alcohol dependence, malnutrition, CKD, pregnancy, HIV more likely to have peripheral neuropathy
-Liver toxicity
-Hepatitis is more common in patients >35yrs old and daily alcohol intake
What are the monitoring requirements for isoniazid and pyrazinamide?
Liver function check before treatment. Further checks only necessary if patients develops any hepatic signs and symptoms.
Renal function check before treatment
What are the main SEs of pyrazinamide?
- Liver toxicity
- Photosensitivity reactions
- Aggravation of gout
- Decreased appetite
What is the main CI of pyrazinamide?
Acute attack of gout
What are the main SEs of ethambutol?
Visual disturbances,
Ocular toxicity: discontinue immediately if deteriorating vision occurs.
What are the monitoring requirements for ethambutol
Test visual accuracy before treating
Check renal function before treatment
Check serum ethambutol: peak levels taken 2-2.5 hours after dose (2-6mg/L) and trough < 1mg/L
List some tetracyclines?
Tetracyclines Limeycline Doxycycline Minocycline Oxytetracycline
What is the mechanism of action of tetracyclines?
Bacteriostatic. Prevent the binding of amino-transfer RNA therefore inhibiting cell growth
What are the CI of tetracyclines
Children under 12 years (due to deposition in growing bones and teeth that causes staining and sometimes dental hyerplasia), pregnancy and breast feeding.
What are the cautions of tetracyclines?
Myasthenia gravis (increases muscle weakness), may exacerbate systemic lupus
What are the SEs of tetracyclines?
Benign intracranial HTN (headache and visual disturbances)-DISCONTINUE.
Hepatoxicity- avoid or use with caution.
Photosensitivity
Blood disorders
Oesophageal irritation
Which tetracyclines do you avoid with milk, indigestion remedies, zinc and iron remedies 2 hours before or after?
And then do you take these()?
‘DOT’
Demecycline
Oxytetracycline
Tetracycline
On an empty stomach
Which tetracyclines are fine with milk?
DLM ‘does like milk’
Doxycycline
Limeocycline
Minocycline
What other medicinal products decrease the absorption of tetracyclines?
Antacids and aluminium, calcium, iron, magnesium and zinc salts
What are the patient and carer advice for tetracyclines?
Swallow whole, with plenty of fluid, while sitting or standing To prevent oesophageal irritation.
Avoid exposure to sunlight and sun lamps
What is the mechanism of action for nitrofurantoin?
Broad spec, bactericidal in the renal tissue
what are the CI and cautions of nitrofurantoin?
CI:
G6PD deficiency, infants less than 3 months old
Cautions:
Anaemia, diabetes mellitus, electrolyte disturbances, low vit B deficiency, suspectability of peripheral neuropathy
when should nitrofurantoin avoided during pregnancy?
avoid at term- may produce neonatal haemolysis.
what are this risks of taking nitrofurantoin in renal impairment?
risk of peripheral neuropathy.
avoid if eGFR<45ml/min
what are the monitoring requirements of nitrofurantoin during long term therapy?
LFTs
Pulmonary symptoms, especially in the elderly (STOP if deterioration in lung function)
what are the advisory labels for nitrofurantoin?
what frequency are they usually taken during the day?
this medicine may colour your urine yellow/brown- it’s normal
take with or just after food
I/R tabs: usually QDS
M/R caps: BD
prophylaxis: OD, usually at night.
what organism commonly causes UTIs?
E.coli
Staphyococcus sapropyticus is common in sexually active young women.
when should a urine sample be collected before starting therapy?
- in men
- pregnant women
- children under 3 years old
- patients with suspected upper UTI
- complicated infection, or recurrent infection
- urine dipstick testing gives a positive result for leucocyte esterase or nitrite
what abx should be taken with or after food?
Metronidazole
nitrofurantoin
label 21
what abx before food/empty stomach?
Demeclocyline Rifampicin (label 22): 30-60 mins after food Oxytetracycline Phenoxymethylpenicillin Flucoxaciliin Ampicillin Tetracycline
what abx should NOT be taken with milk?
'’C DOT’’
Ciprofloxacin
Demeclocyline
Tetracycline
Oxytetracycline
what abx are fine with milk?
'’DLM’’
doxycycline
lymecycline
minocycline
