Aminoglycosides & other drugs Flashcards
(119 cards)
1
Q
Examples of Aminoglycosides?
A
- Amikacin
- Gentamicin
- Neomycin
- Streptomycin
- Tobramycin
2
Q
Which aminoglycosides are active against pseudomonas aeruginosa?
A
TAG
- Tobramycin
- Amikacin
- Gentamicin
3
Q
How is Tobramycin administered?
A
Administered via nebulisation or inhalation
4
Q
What is pseudomonas aeruginosa?
A
An organism that causes pneumonia, infections in the blood etc.
5
Q
What is streptomycin active against?
A
Streptomycin is active against mycobacterium tuberculosis and reserved almost entirely for tuberculosis.
6
Q
In what form must Streptomycin be given in and why?
A
As an injection because it cannot be absorbed from the gut
7
Q
What is the preferred aminoglycosides?
A
Gentamicin because it is used to treat many infections including eye/ear infections, pneumonia etc.
8
Q
What is the usual dose for aminoglycoside?
A
Once daily is preferred
Parenteral treatment should never exceed 7 days whenever possible.
9
Q
What is the contraindication for aminoglycosides?
A
Myasthenia gravis - causes aminoglycosides to impair neuromuscular transmission.
10
Q
What are the side effects of Aminoglycosides?
A
- Ototoxicity
- Nephrotoxicity
- Neurotoxicity
- Risk in pregnancy (auditory nerve damage in infants)
- Skin reactions
- Nausea and vomitting
11
Q
What are the signs of Ototoxicity?
A
- Tinnitus or ringing in ears
- Hearing loss
- Dizziness
- Uncoordination in movements
- Vestibular damage
12
Q
What are the signs of Nephrotoxicity?
A
- Decreased urine output
- Fluid retention (swelling in legs, ankles or feet)
- Fatigue
- SOB (shortness of breathe)
13
Q
Which drugs cannot be used alongside Aminoglycosides?
A
- Loop diuretics
- Cephalosporins, ciclosporin or vancomycin
14
Q
Can loop diuretics be used alongside with Aminoglycosides and why?
A
No, because the risk of ototoxicity is increased when used alongside each other
15
Q
Can cephalosporins, ciclosporin
or vancomycin be used alongside aminoglycosides and why?
A
No because risk of nephrotoxicity is increase when used alongside each other
16
Q
What are the monitoring requirements for aminoglycosides?
A
- Plasma concentration
- Renal function (esp in the elderly) - as they are renally excreted
- Auditory and vestibular function
Serum concentration monitored in patients receiving parental aminoglycosides.
Monitored in elderly, obesity, cystic fibrosis, renal impairment or high dose.
17
Q
Which individuals need dose adjustments for aminoglycosides?
A
Patients with renal impairment
18
Q
What dose adjustments must be made for people with renal impairment taking aminoglycosides?
A
- Increase dose interval
But if renal impairment is severe - decrease dose
19
Q
When should blood samples be taken for people on aminoglycosides?
A
Approximately 1 hour after administration (peak concentration) and just before next dose (trough concentration).
20
Q
What is peak concentration?
A
The highest concentration of a drug in the blood after dose is given (1 hr after admin)
21
Q
What is trough concentration?
A
The concentration of drug in the blood immediately before the next dose is administered
22
Q
What must be done if the trough concentration is high?
A
Increase dose interval
23
Q
What must be done if the peak concentration is high, within range and below range?
A
High - Decrease the dose
Within range - maintain dose
Below range - increase dose
24
Q
What should be the peak and trough concentrations for Aminoglycosides?
A
For IM or IV use for multiple daily regimens:
- Peak concentration: 5-10mg/L
- Trough concentration: <2mg/L
For multiple daily regimens in endocarditis:
- Peak concentration: 3-5mg/L
- Trough concentration: <1mg/L
25
Which aminoglycosides can be used in gentamicin-resistant bacteria?
Amikacin
26
Which aminoglycoside is more stable to enzyme activation than gentamicin?
Amikacin
27
Which Aminoglycoside are too toxic for parenteral administration?
Neomycin sulfate
28
What MHRA warning/advice is attached to Aminoglycosides?
Aminoglycosides increase the risk of deafness [ototoxicity] in patients with mitochondrial mutations.
Potential histamine-related adverse drug reactions (like rashes) with some batches - caution with pts on drugs which release histamine (e.g opioids).
29
What are carbapenems?
Beta lactam antibiotics and they are structurally similar to penicillin and cephalosporins.
They are broad spectrum.
30
What are examples of Carbapenems?
Ertapenem, Imipenem, Doripenem, Meropenem
31
What are Imipenem and Meropenem used for?
Used for severe hospital acquired infections like: septicaemia, complicated UTI, Hospital acquired pneumonia (HAP) etc.
32
What must Imipenem be given with and why?
It must be given with Cilastatin because Imipenem is partially inactivated by kidney enzymes
33
Do Meropenem, Doripenem and ertapenem need to be given with cilastatin?
No because they are stable in renal enzymes
34
What are the side effects of Carbapenems?
- Diarrhoea
- Headache
- Nausea
- Vomiting
35
Cautions for carbapenems?
Caution in pts with sensitivity to beta lactam antibacterials.
36
What are cephalosporins?
Broad-spectrum antibiotics.
Structurally similar to penicillin.
37
Examples of 1st Generation Cephalosporins?
- Cefalexin
- Cefadroxil
- Cefradine
38
What do all 1st generation cephalosporins begin with?
Cefa / Cefra
Except for Cefaclor
39
Examples of 2nd generation cephalosporins?
Furry fox face
- Cefuroxime
- Cefoxitin
- Cefaclor
40
Examples of 3rd generation Cephalosporins?
- Cefotaxime
- Ceftazidime
- Ceftriaxone
- Cefixime
41
What do all 3rd generation cephalosporins contain?
The letter 'T'
42
How are cephalosporins excreted?
Excreted renally
43
What are the indications for Cephalosporins?
* Septicaemia
* Pneumonia
* Meningitis
* Biliary tract infections
* Peritonitis
* UTI
44
Which Cephalosporins can be used to treat infections of the CNS like meningitis?
Third generations -
Cefotaxime & Ceftriaxone
45
What are the side effects for Cephalosporins?
* Hypersensitivity – approximately 0.5 – 0.6% of penicillin-sensitive patients are also sensitive to cephalosporins.
SO IF PATIENT IS ALLERGIC TO PENICLLIN, DO NOT GIVE CEPHALOSPORINS!
* Antibiotic associated colitis (mainly presented as diarrhoea)- this is more common in 2nd and 3rd generation cephalosporins
46
What is the drug action for Vancomycin?
It is a glycopeptide antibacterial.
Bactericidal activity against aerobic and anaerobic for only gram positive bacteria - so narrow spec antibiotic
47
What is Vancomycin used for?
Commonly used to treat antibiotic associated colitis caused by C. diff infection
48
How should Vancomycin be adminstered?
Preferably by IV route because it is not absorbed effectively via the oral route
49
What are the initial doses and subsequent doses of Vancomycin based on?
Initial doses are based on body weight.
Subsequent doses are based on serum-vancomycin concentration.
50
What is the Trough concentration range for Vancomycin?
10-20mg/L
51
What must be monitored when taking Vancomycin?
* Monitor FBC, renal, and hepatic function
* Monitor vestibular and auditory function (avoid concurrent use of ototoxic drugs like furosemide)
52
What are the side effects of Vancomycin?
* Agranulocytosis
* Dizziness
* Neutropenia
* Drug fever
* Hypersensitivity
* Ototoxicity
* Skin reactions
* Nephrotoxicity - higher risk than teicoplanin
* Red man syndrome - infusion related reaction
* Tinnitus - discontinue drug if this occurs
53
What is Clindamycin active against?
Active against gram positive bacteria
It is a narrow spec
54
What are the indications for Clindamycin?
- Bone and joint infections (joint infection, osteomyelitis, peritonitis bone).
- Alternative to macrolides, especially in penicillin-sensitive patients
55
What is contraindicated with Clindamycin?
- Diarrhoeal states
If patient starts getting diarrhoea, only with this antibiotic though, they must stop the medication straight away as clindamycin causes serious colitis.
Contact the doctor straight away
56
What are the side effects of Clindamycin?
- Fatal antibiotic-associated colitis - usually occurs with clindamycin
- Discontinue if c-difficile infection is suspected or confirmed (diarrhoea, watery, stool)
57
When should Clindamycin be discontinued?
* Discontinue if C. diff infection is suspected or confirmed.
* Discontinue if diarrhoea occurs and contact GP.
58
What must be monitored with Clindamycin?
Monitor liver and renal function if treatment exceeds 10 days
59
Examples of Macrolides?
Azithromycin, clarithromycin, and erythromycin
60
What is the mechanism of action for macrolides?
Bacteriostatic (stops bacterial cell growth)
It is broad spec and the alternative for penicillin allergic pts.
61
What are the common indications for Macrolides?
* Respiratory and skin/soft tissue infections
* Severe pneumonia
* Eradication of H. Pylori
62
What are the interactions of macrolides?
When taken with warfarin or simvastatin, their plasma concentration is increased.
63
What are the side effects of Erythromycin and its cautionary labels?
Nausea, vomiting and diarrhoea.
Cautionary labels: 5, 9 & 25
64
What are the contraindications and cautions for Erythromycin?
Hepatic impairment - may cause hepatoxicity
Renal impairment - can cause ototoxicity in adults and children at high doses
It is the macrolide preferred in pregnancy and breastfeeding but only when benefits outweighs the risk.
65
Which macrolide is preferred?
CLARITHROMYCIN because it has a slightly higher activity compared to erythromycin.
It is also more stable, and causes fewer side effects.
66
Which macrolide is the least active?
Azithromycin - less active over gram-positive bacteria but has enhanced activity over some gram-negative bacteria
67
What is the usual dose for Azithromycin?
Once daily dosage due to long tissue half life
68
What are the cautionary labels for Azithromycin?
5,9 and 23 for capsules
69
When can Azithromycin be given over the counter?
Max single dose if 1g, max daily dose of 1g and pac size of 1g.
70
What are the important information for Clarithromycin?
It is more commonly prescribed because Erythromycin has greater activity, it is more stable and has fewer side effects.
Usual dose is twice daily.
Avoid in 1st trimester; only use in 2nd n 3rd if benefit outweighs the risk.
Hepatic and renal impairment - avoid.
Cautionary labels: 9,21, 25, 13
71
What is used to treat Lyme disease?
Erythromycin, azithromycin and clarithromycin.
72
What are the five classes of penicillin?
1) Beta-lactamase sensitive (penicillin V, penicillin G)
2) Penicillinase-resistant penicillins (flucloxacillin)
3) Broad-spectrum penicillins (amoxicillin, ampicillin, co-amoxiclav)
4) Antipseudomonal penicillins (piperacillin, ticarcillin)
5) Mecillinam-type penicillins (pivmecillinam)
73
How do pencillins work?
They are bacteridial and intefere with cell wall synthesis
74
When should penicillin be stopped?
If anaphylaxis, hives, or an immediate rash occurs to penicillin
75
What must be given instead of penicillin if there's a reaction?
Macrolide can be given if there's a if anaphylaxis, hives, or an immediate rash occurs to penicillin
76
Examples of Quinolones?
Ciprofloxacin, Ofloxacin, Norfloxacin, Nalidixic acid
77
What are the examples of convulsions?
- May induce convulsions (reduces seizure threshold) in people with or without a history of convulsions
- Can cause tendon damage (risk increased over the age of 60)
78
What drug when taken with Quinolones can increase the risk of convulsions?
NSAIDs can increase the risk of convulsions
79
What drug when taken with Quinolones can increase the risk of tendon damage?
Corticosteroids can increase the risk of tendon damage, when taken with Quinolones
80
When must Quinolones be discontinued?
If tendonitis is suspected
81
Examples of Tetracyclines?
Demeclocycline, Doxycycline, Lymecycline, Minocycline, Oxytetracycline
82
What are the common indications for Tetracyclines?
* Acne
* Pneumonia
* Chlamydia
* Rickettsia
* MRSA infections
83
What are the side effects of Minocycline?
It has a greater risk of lupus-like syndrome, and can sometimes cause irreversible skin pigmentation
84
What are the side effects of Tetracyclines?
* Intracranial hypertension (discontinue if headaches or visual disturbances occur)
* Photosensitivity reactions (especially with doxycycline and demeclocycline)
* Discolouration of tooth enamel in children (not to be used in children under 12)
* Dysphagia and oesophageal/stomach irritation
85
What are the indications of Trimethoprim?
It is an antifolate used for:
- UTI
- Respiratory tract infections (chronic bronchitis, pneumonia)
86
What is the mode of action for Trimethoprim?
Bacteriostatic
Folate antagonist
87
When should Trimethoprim be avoided?
- Pregnancy - it is teratogenic; so avoid esp in 1st trimester but in general
- Breastfeeding (but short term use is not known to be harmful
- Children under 12
- Patients with blood disorders
88
What is the side effect of Trimethoprim?
- Blood disorders
- Diarrhoea
- Electrolyte imbalance
- Fungal overgrowth
- Headache
- Nausea
- Skin reactions
- Vomiting
89
What must be monitored when taking Trimethoprim?
Monitor FBC in long-term therapy
90
What patient & carer advice must be given with Trimethoprim?
Advise on how to recognise signs of blood disorders - fever, sore throat, rash, mouth ulcers, purpura, bruising or bleeding develops - seek immediate medical attention
Cautionary label - 9
91
What dose adjustment needs to be done for Trimethoprim?
In adults:
Manufacturer advises dose reduction to half normal dose after 3 days if eGFR 15–30 mL/minute/1.73 m2.
Manufacturer advises dose reduction to half normal dose if eGFR less than 15 mL/minute/1.73 m2.
In children:
Manufacturer advises dose reduction to half normal dose after 3 days if estimated glomerular filtration rate 15–30 mL/minute/1.73 m2.
Manufacturer advises dose reduction to half normal dose if estimated glomerular filtration rate less than 15 mL/minute/1.73 m2.
92
What is the indication of Metronidazole?
Used to treat:
- trichomoniasis
- bacterial vaginitis
- vaginosis
It is the first-line treatment for gingivitis (200mg TDS for 3 days)
- Can also be used to treat C.diff infection
93
What is metronidazole an alternative for?
An alternative for penicillin to treat oral infections.
94
What is topical metronidazole used for?
To reduce microbial odours and rosacea
95
What caution is linked to Metronidazole?
It can produce a disulfiram-like reaction with alcohol - vomiting, flushing, throbbing headache, hang over like symptoms
SO AVOID ALCOHOL
96
What are the side effects of metronidazole?
- Nausea & Vomiting
- Taste disturbances
- Anorexia
97
What are the various treatments for uncomplicated UTI?
* Nitrofurantoin (AVOID AT TERM)
* Trimethoprim (AVOID IN PREGNANCY)
* Amoxicillin, ampicillin, or an oral cephalosporin
98
Can nitrofurantoin be given in pregnancy?
Yes but avoid at term (3rd trimester
99
When should Trimethoprim be avoided?
Avoid in pregnancy
100
How long is the treatment for uncomplicated UTI for nitrofurantoin?
3 day treatment
7 days in males and pregnant women.
101
What is the side effect of Nitrofurantoin?
Can discolour the urine - turn it into a dark yellow / brownish colour.
102
What is the contraindication and caution of nitrofurantoin?
Contraindication: Acute porphyria, G6PD deficiency, infants less than 3 months
Caution: Anaemia, diabetes, electrolyte imbalance, folate deficiency, pulmonary disease, vitamin B deficiency
103
What must be done for patients with renal impairment for nitrofurantoin?
Avoid if eGFR is less than 45ml/min/1.73
Can be used with caution if eGFR 30-44ml/min/1.73 as a short course ONLY (3-7 days), to treat uncomplicated lower urinary-tract infection caused by suspected or proven multidrug resistant bacteria and only if potential benefit outweighs risk.
104
What must be monitored with nitrofurantoin?
- Liver function (discontinue if liver function decreases)
- Pulmonary symptoms like fever, chills, cough, chest pain, dyspnoea, pulmonary infiltration, eosinophilia and pleural effusion.
Esp in elderly patient
105
What is Linezolid?
It is a reversible, Monoamine oxidase inhibitor (MAOIs) antibacterial drug.
It is also an antidepressant but the dose used for antibiotic doesn't have an antidepressant effect.
106
What should be avoided with patients taking Linezolid and why?
Consuming large amounts of tyramine-rich foods as it could cause hypertensive crisis
107
What are examples of tyramine rich food?
Mature cheese, salami, pickled herring, Bovril
108
What are the side effects of Linezolid?
* Severe optic neuropathy (visual impairment) particularly if used longer than 28 days
* Blood disorders
109
What should be monitored when taking Linezolid?
* Monitor FBC (including platelet count) weekly.
* Monitor blood disorders
110
What patient and carer advice should be given with Linezolid?
Report symptoms of visual impairment - blurred vision, visual field defect, changes in colour vision and visual acuity.
111
How is Tuberculosis treated?
It is treated in two phases:
* Phase ONE (Initial Phase) – 4 drugs for 2 months (RIPE - rifampicin, isoniazid, pyrazinamide, ethambutol)
* Phase TWO (Continuous Phase) – 2 drugs for 4 months (RI - rifampicin and isoniazid)
112
What side effect is linked to all TB drugs?
Hepatoxicity - expect for Ethambutol
Discontinue if signs of liver disorder develop.
113
What is the mechanism of action for Rifampicin?
It is an enzyme inducer
114
What is the side effect for Rifampicin?
* Discolours soft contact lenses
* Colours urine orange/red
This is patient n carer advice as well
115
What is the side effect for Isoniazid?
May cause peripheral neuropathy.
Give pyridoxine hydrochloride (vitamin B6) for prophylaxis.
116
What must be given for Prophylaxis of the Isoniazid side effect?
Pyridoxine hydrochloride (vitamin b6)
117
What is the side effect for Ethambutol?
Causes visual side effects
Discontinue if there is any visual deterioration.
118
What must be monitored for TB?
- Monitor signs of hepatoxicity - jaundice, itching, fatigue, abdominal pain, nausea n vomiting
* Check renal and hepatic function prior to treatment
* Patients with pre-existing liver disease and/or alcohol dependence should have frequent liver checks, particularly in the first 2 months.
* If there is no liver disease, further checks are only necessary if the patient has fever, malaise, vomiting, jaundice, or unexplained deterioration.
119
