Pharmacology in Dentistry Flashcards

What is the mechanism of action of non-steroidal anti-inflammatory drugs (NSAIDs) in dentistry?

Answer: Inhibit cyclo-oxygenase (COX) enzymes, reducing prostaglandin synthesis, decreasing pain, inflammation, and fever

NSAIDs (ibuprofen, diclofenac) inhibit COX-1 and COX-2, reducing prostaglandin synthesis at sites of inflammation. This reduces sensitisation of peripheral nociceptors, providing analgesic and anti-inflammatory effects.

According to the BNF, what is the first-line analgesic for post-extraction dental pain?

Answer: Ibuprofen 400 mg three times daily (if not contraindicated) or paracetamol 1g four times daily

For post-extraction pain, ibuprofen 400 mg TDS is first-line if no contraindications. Paracetamol 1g QDS is used if NSAIDs are contraindicated. Combination (ibuprofen + paracetamol) provides superior analgesia to either alone.

What antibiotic is recommended by SDCEP guidelines for dentoalveolar infections with systemic features?

Answer: Amoxicillin 500 mg three times daily for 5 days (or metronidazole 400 mg TDS if penicillin allergic)

Scottish Dental Clinical Effectiveness Programme (SDCEP) and NICE guidelines recommend amoxicillin as first-line antibiotic for acute dentoalveolar infection with systemic spread. Metronidazole or phenoxymethylpenicillin are alternatives.

What is the recommended management of a patient on warfarin requiring a simple dental extraction?

Answer: Do NOT stop warfarin; check INR within 24–72 hours of procedure; if INR ≤4.0 proceed with local haemostatic measures (packing, sutures, haemostatic dressings)

SDCEP/NICE guidance: patients on warfarin should NOT routinely stop their anticoagulation for simple extractions. Check INR within 72 hours. If ≤4.0, proceed with local haemostatic measures. Stopping warfarin risks systemic thromboembolism.

What is the clinical significance of prescribing metronidazole to a patient drinking alcohol?

Answer: Metronidazole inhibits acetaldehyde dehydrogenase causing a disulfiram-like reaction: flushing, nausea, headache, and cardiovascular effects with even small amounts of alcohol

Metronidazole blocks acetaldehyde dehydrogenase, causing acetaldehyde accumulation when alcohol is consumed. This disulfiram-like reaction causes severe flushing, nausea, vomiting, headache, and palpitations.

What is the pharmacological basis for prescribing prophylactic amoxicillin before dental procedures?

Answer: Current NICE guidance (NG178, 2008 updated) no longer recommends routine antibiotic prophylaxis for infective endocarditis in at-risk patients undergoing dental procedures in the UK

NICE guideline NG178 (2008, updated 2016): antibiotic prophylaxis for infective endocarditis prevention is NOT recommended for any dental procedure in at-risk patients in the UK — in contrast to previous practice and some international guidelines.