Antibiotic use and abuse Flashcards
How should most oral infections be resolved?
Removal of the cause and establishment of drainage (removal of tooth or opening up the pulp chamber or drainage of abscess)
Why should antibiotics not be prescribed for oral infections?
Can cause harm. May be a temporary solution to infection but do not deal with cause
Will antibiotics ever help pulpits?
No
How can antibiotics cause harm directly?
Fatal anaphylaxis to pencillins
Hypersensitivity reactions
Adverse drug reactions
How can antibiotics cause harm indirectly?
Opportunistic infections e.g. c. diff (commensal bacteria in gut die and c. diff thrives) Resitant organisms (MRSA)
Contraindications to antibiotic use?
Absolute and relative
Absolute - known hypersensitivity
Relative - liver disease (affects metabolism)
Kidney disease (tetracylines may worsen renal failure)
Lymphocytic leukaemia, glandular fever - ampicillin and amoxicillin may cause rash
Pre-existing diarrhoea
What should be kept in mind when prescribing antibiotics to pregnant or lactating women?
Teratogenic effects on developing fetus
Pharmokinetic or phrarmodynamic alterations
Lactation can effect effectiveness
Breastfed infants exposed to maternal drugs
List the categories of adverse effects of antibiotics?
Hypersensitivity/ allergy
Minor adverse drug reaction
Major adverse drug reactions
Developmental
What is allergy mediated by? (2)
Antibodies (type I-III) or T cells (type IV)
What is the problem with antibiotics and patients on warfarin?
Drug interactions - most antibiotics increase effect of warfarin and bleeding risk is increased
What are the 2 uses of antibiotics in dentistry?
Therapeutic (primary or adjunct therapy)
Prophylactic
What is the first choice for antibiotics in dentistry? When is it used?
Amoxicillin
Adjunct treatment of dent-alveolar infection, limit spread of infection.
Prevention/treatment of infection in oro-antral communication
Loading dose prior to implant or extraction for high risk of infection patients
What antibiotic id the first choice in necrotising periodontal disease and periocoronitis?
Metronidazole (anaerobic flora)
What is an appropriate alternative to amoxicillin if the patient is allergic to pencillin?
Metronidazole, clindamycin (more side effects)
Patient has very severe infection, what should you prescribe whilst waiting for clinical treatment?
Amoxicillin and metronidazole (if very severe - to widen the spectrum fo activity to be more effective against anaerobes)
Why is erythromycin not often used as an alternative to amoxicillin in patients allergic to penicillin?
Some oral bacteria have developed resistance
For infections not responding to first line treatment what antibiotics can be given? What is the problem with these?
Clindamycin and co-amoxiclav - GI side effects
What should you always do along side prescribing antibiotics?
Treat the cause (either at practice or refer to specialist)
Why is amoxicillin first choice?
Broad spectrum
When should you not prescribe amoxicillin?
If patient is allergic to penicillin
When antibiotics are used as adjunct treatment, what are they used alongside?
Operative treatment
List 3 procedures where prophylactic antibiotics may increase success?
Tooth transplantation
Prevention of osteoradionecrosis
advanced implantology
Are antibiotics appropriate for alveolar osteitis?
No - this is a fibrinolytic condition
Are antibiotics appropriate for inflammatory conditions? List 2 conditions you may see on clinic?
No
Early pericoronitis
Post-op oedema
What kind of infection are antibiotics effective against/
Bacterial only
4 principles of the use of antibiotics to prevent wound infection?
- Probability of wound infection must be high
- Select appropriate antibiotic
- Initiate therapy at correct time
- Use for appropriate length of time
Within dentistry what are the most likely causes of decreased patient resistance (increased probability of infection)?
Immunocompromised
Immunosupression
Previous jaw radiotherapy
Prophylactic antibiotics to prevent infection of wound must be given at the correct time - when is this?
Must achieve high levels of AB in blood clot, so needs to be high at end of surgery.
Clot impenetrable to AB 3 hours after formation
Give AB 1 hour before surgery
How to reduce antibiotic resistance?
Minimise unnecessary prescribing - treat cause
Correct AB for correct duration
Complete entire course of treatment
