drug use in dentistry

Question 1

name 2 hazards of drug use

Answer 1

1) death
- allergy
- toxicity

2) drug interactions
has an effect on the metabolism / absorption of other essential medicines such as warfarin (anticoagulant) and carbamazepine (anticonvulsant)

Question 2

name 5 drug classes

Answer 2

1. local anaesthetics
2. antimicrobials
3. drugs in pain and inflammation
4. drugs used in sedation
5. emergency medical drugs

Question 3

what is the function of local anaesthetics

Answer 3

reduces awareness of pain

act on nerve ion channels to block propagation

Question 4

name 4 local anaesthetics

Answer 4

lignocaine (lidocaine)
prolocaine
bupivicaine
mepivicaine

Question 5

why do local anaesthetics often need vasoconstrictors added to them

Answer 5

LA are often vasodilators which open the blood flow
opening the blood flow washes the drug away from the area where you need it to act
adding a vasoconstrictor will prolong the action of the drug where you want it as it will slow down blood flow

Question 6

name 3 antimicrobials

Answer 6

1. antibiotics (bacteria)
2. antiviral
3. antifungals

Question 7

name 4 antibiotics

Answer 7

1. amoxycillin
2. metronidazole
3. doxicycline
4. clindamycin

Question 8

name an antiviral drug

Answer 8

aciclovir

can be used topical or systemic

Question 9

what does systemic mean

Answer 9

drug gets distributed all over the body

usually in tablet form

Question 10

what does topical mean

Answer 10

drug is just applied to one area

eg coldsore on lip

Question 11

name antifungal drugs and state whether they are topical or systemic

Answer 11

nystatin = topical
fluconazole = systemic (oral)

Question 12

what does analgesic mean

Answer 12

painkiller

Question 13

what type of drugs are used in treating pain and inflammation

Answer 13

–> drugs used to reduce the inflammatory mediators
eg NSAIDs

–> drugs used to reduce the inflammatory process
eg corticosteroids

Question 14

what does NSAID stand for

Answer 14

non-steroidal anti-inflammatory drugs

Question 15

describe paracetamol and it’s actions

Answer 15

anti-pyretic
analgesic
can be got over the counter - unrestricted
few side affects
dose = 1g 4 times daily
can be combined with other analgesics eg co-codamol = paracetamol and codiene

Question 16

give examples of NSAIDs

Answer 16

• salicylates eg aspirin
• propionic acid derivatives eg ibuprofen
• phenylacetic acid derivatives eg diclofenac

Question 17

describe how NSAIDs work

Answer 17

true action unknown
inhibit prostaglandin synthesis
change the balance of PGE1 and PGE2 (anti-inflammatory)
cyclo-oxygenase (COX) enzyme inhibition 
COX1 inhibitors = aspirin, ibuprofen
COX2 inhibitors usually not as helpful

Question 18

describe aspirin

Answer 18

• available without restriction = over the counter
• NSAID
• pharmacokinetics - rapid absorption from GIT, elimination from 1st order kinetics (unless overdose - enzyme saturation, toxic effects - acidosis)
• inhibits COX1 = reduced synthesis of prostaglandins,
  reduced production of inflammatory mediators, anti-pyrexic
• can be taken in anticipation of pain (before a procedure) = pre-emptive analgesia

Question 19

what are the side effects of aspirin

Answer 19

> gastric irritation = erosions, ulceration (worse with alcohol)

> inhabitation of platelet functioning = enhanced bleeding

> bronchospasm = exacerbate asthma

> allergic reaction = rash

> drug interactions = significant protein binding, warfarin potentiation

Question 20

describe ibuprofen

Answer 20

• sold without restriction = over the counter
• NSAID
• same actions as aspirin
• dose: 200-600mg 3 times daily
• fewer side effects than aspirin
  (less people suffer the side effects of ibuprofen but those who do have problems are just as bad as aspirin)

Question 21

describe diclofenac

Answer 21

• prescription only = not over the counter
• more potent than ibuprofen
• more effective anti-inflammatory action
• dose: 50mg 3 times daily
• side effects are worse = higher incidence of gastric bleeding, higher incidence of asthma triggering, allergic reaction (rash)

Question 22

how do corticosteroids reduce inflammation

Answer 22

they inhibit:
- capillary permeability

• formation of bradykinins
• migration of white blood cells
• reduce eicosanoid synthesis

suppresses features of inflammation but doesn’t address the problem

Question 23

give examples of topical corticosteroids

Answer 23

• steroid inhaler = asthma
• hydrocortisone cream = eczema
• steroid treatments for mouth ulcers such as
  >Beclomethasone inhalers
  >Hydrocortisone adhesive tablets
  >Betamethasone solutions

Question 24

give examples of systemic corticosteroids

Answer 24

• prednisolone (tablets) = prevent transplant rejection and treat immunological diseases
• dexamethasone (injection) = reduce swelling after injury eg after wisdom tooth removal

Question 25

what are the side effects of systemic corticosteroid use

Answer 25

the longer you take the steroids the more consequences there are - high blood pressure - weight gain (fluid) - fat distribution change (centripetal obesity and buffalo hump) - gastric ulceration - adrenal suppression - osteoporosis - diabetes

Question 26

what do anxiolytics do

Answer 26

reduce anxiety, used in sedation

Question 27

name 2 anxiolytics

Answer 27

1) benzodiazepines (taking every day will lead to addiction, make you forget what happened) - diazepam - midazolam 2) gas - nitrous oxide

Question 28

how does benzodiazepines work

Answer 28

they stick onto GABA receptors and change the ion flow in cells

Question 29

describe how nitrous oxide works

Answer 29

- inhaled as a gas - no needle technique - can adjust the amount used during the procedure - changes the way cells speak to each other but not sure how this happens - no organ metabolism issues - interferes with folic acid metabolism = don't use during pregnancy