Pharmacology and the dental patient

Question 1

Name some commonly used analgesics

Answer 1

• Ibuprofen
• Paracetamol
• Aspirin
• Corticosteroids
• Codine

Question 2

What is an con of ibuprofen

Answer 2

• Occasionally causes xerostomia (dry mouth) which can increase oral plaque and dental caries (cavities)

Question 3

What is the use of Corticosteroids

Answer 3

Anti-inflammatory medications that are used to relieve discomfort and soreness of the mouth

Question 4

What may be given if pain is more severe

Answer 4

Narcotic analgesics - codeine, hydrocodone

Question 5

What is the role of CYP2D6

Answer 5

The conversion of codeine to its active metabolite morphine occurs in the liver, and is catalysed by CYP2D6

Question 6

What’s the effect of being a poor metaboliser of CYP2D6 in relation to taking codeine

Answer 6

• As codeine is a prodrug, poor metabolisers of CYP2D6 will experiences little to no analgesia from the medication
• This is because they lack the enzyme to metabolise the drug

Question 7

What’s the issue with being a Poor Metaboliser (PM)

Answer 7

PM have inadequate pain control due to very minimal conversion of codeine (prodrug) to morphine

Question 8

What’s the issue with being an Ultrarapid Metaboliser (UM)

Answer 8

• Likely to have more side effects from higher morphine concentrations
• Can be life-threatening

Question 9

What is Pharmacogenetics

Answer 9

The identifications of genetic variants that affect the responses to medications in patients

Question 10

Name some drugs for sedation

Answer 10

• Nitrous oxide
• Midazolam

Question 11

Describe Nitrous Oxide

Answer 11

• Main use is usually as a mild sedative + analgesic
• Helps to alleviate patient anxiety

Question 12

What are the 4 levels of sedation with Nitrous Oxide

Answer 12

1. A tingling sensation
2. Warm sensations
3. A feeling of well-being/euphoria
4. Sleepiness

Question 13

Describe Midazolam

Answer 13

• IV sedation, recommended for adults
• Has a fast onset (1-2 mins)
• Drug slows heart rate and rate of breathing
• Patient can leave the surgery 1-1.5 hours after
• Can become addictive

Question 14

What are the 2 phases of sedation with Midazolam

Answer 14

1. Recovery from sedation
2. Recovery from psychomotor impairment

Question 15

What are some localised oral lesions that are indicated for antibiotic use

Answer 15

• Periodontal abscess
• Acute necrotising ulcerative gingivitis

Question 16

What does short-course antibiotic therapy require in terms of characteristics

Answer 16

• Rapid onset of action
• Bactericidal activity
• Easy penetrability
• Administration at an optimal dose

Question 17

What may prolonged courses of antibiotics result in

Answer 17

• Normal resident oral flora being destroyed
• Selection of resistant strains
• Colonisation by harmful micro-organisms that aren’t normal residents

Question 18

What is Metronidazole and what can it be indicated for

Answer 18

• Used particularly for anaerobic bacteria + protozoa
• Can be indicated for treatment of a bacterial dental infection (often used with Amoxicillin)

Question 19

When should you not take Metronidazole whilst consuming alcohol

Answer 19

Effects include:
- Nausea
- Vomiting
- Flushing of skin
- Shortness of breath

Question 20

Describe antihypertensives and postural hypotension

Answer 20

• Postural hypotension is an excessive fall in blood pressure when an upright position is assumed
• Symptoms: faintness, light-headedness, dizziness, confusion

Question 21

Describe opioids and addiction-related behaviour

Answer 21

• Opioid analgesics are sometimes used for some forms of chronic orofacial pain
• With long-term opioid therapy for chronic pain, there’s the potential risk of developing opioid tolerance, dependance or addiction

Question 22

Describe insulin and oral hypoglycaemics

Answer 22

• Most common complication of diabetes therapy that can occur in the dental surgery is a hypoglycaemic episode (drop in blood glucose levels)
• Oral infections or dental procedures can affect food intake in diabetics

Question 23

Describe steroids

Answer 23

• Chronic usage of steroid inhalers make the patient susceptible to oral yeast infection + blood blisters

Question 24

Describe beta blockers

Answer 24

• Patients medicated with non-selective beta blockers have heightened sensitivity to the systemic effects of vasopressors
• Beta blockers can decrease hepatic blood flow and/or inhibit hepatic enzymes, resulting in the reduced metabolism of lidocaine

Question 25

Describe warfarin and antiplatelet drugs

Answer 25

• Warfarin is an anticoagulant which inhibits synthesis of the vitamin K-dependant coagulation factors
• A normal coagulation profile has an INR of 1.0, the risk of bleeding increases exponentially as the INR rises
• INR should be measures within 72 hours prior to the operative procedure - allows time for any dose adjustment so the INR is less than 4.0 on the day of procedure

Question 26

Describe bisphosphonates

Answer 26

• Bisphosphonates are used to prevent bone resorption in osteoporosis and bone cancer
• Bisphosphonate usage is associated with exposure of dead bone in jaws
• By surpressing bone resorption, any damaged bone will be left in situ instead of being resorbed