Types of Medications, Analgesics

Analgesics in Dentistry

Analgesics

• Analgesics don't address the cause of pain; use when pain can't be eliminated by dental treatment.
• Use the lowest possible dose for the shortest timeframe.
• Recommend as a 'course of treatment' to maintain blood levels above the threshold for effective pain relief.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

• Have anti-inflammatory and analgesic properties.
• Inhibit prostaglandin production via the arachidonic acid pathway.
• Act on the PNS and CNS.
• Effective for acute pain and inflammation related to dental procedures and TMJ dysfunction.
• Side effects depend on dosage and duration.
• First choice for acute dental pain.
• Non-selective: Ibuprofen, Naproxen
• COX2 selective: Celecoxib
• Patients to avoid:
  • Severe kidney impairment (eGFR < 30 mL/min)
  • Severe heart failure
  • Active GI ulcer or bleeding
  • Bleeding disorders
  • Taking corticosteroids or anticoagulants
  • Multiple risk factors for increased NSAID toxicity (e.g., elderly with GI bleeding history)

Ibuprofen

• Dose: $400$ mg orally, every 6-8 hours.
• Preferred for acute nociceptive dental pain, due to anti-inflammatory properties.
• Before prescribing, determine risk factors.
• Minimize harm:
  • Take regularly, not as needed.
  • Use for the shortest duration possible (<= 5 days).
  • Combine with paracetamol, then use paracetamol alone.
  • Seek review if needed after 5 days.
• Long-term use/high doses increase GI and renal risks.
• Adverse Effects: GI disturbances, fluid retention.
• Drug Interactions: May interfere with antihypertensive medications if taken for > 1 week.

Paracetamol

• Has analgesic and antipyretic actions.
• Low incidence of adverse effects; overdose can cause hepatotoxicity.
• Drug of choice when NSAIDs are contraindicated.
• Effective for mild pain, particularly of soft tissue and musculoskeletal origin; mild to moderate post-treatment pain; severe pain (to supplement opioids); fever.
• Dose: $500-1000$ mg every 4-6 hours (max $4000$ mg daily).
• Peak blood levels: $0.5-1.5$ hours.
• Half-life: $2-3$ hours; primary biotransformation in the liver.
• Children: $15$ mg/kg orally every four hours (max $90$ mg/kg up to $4000$ mg).
• Can be combined with NSAIDs or opioids.
• Does not cause gastric irritation like aspirin/NSAIDs.
• Adverse effects: Liver disease, increased toxicity with alcohol.
• Overdose: Hepatotoxicity, hypoglycaemia, acute renal tubular necrosis.

Opioids

• Activate opioid receptors, inhibiting neuronal activity and pain transmission.
• Act on CNS and PNS.
• High incidence of adverse effects.
• Interactions/Precautions: MAOIs, potentiation of sedative/depressant effects with other CNS depressants (sedatives, hypnotics, phenothiazines, anaesthetics, alcohol).
• Generally used for severe pain.
• Examples: Oxycodone, tramadol, and tapentadol.
• Adjunctive analgesics, not primary, for ambulatory patients.
• Use Codeine with caution as it is no longer recommended; oxycodone is preferred.

Pain Relief Strategies

• Effective pain management: accurate diagnosis, appropriate treatment plan using the '3 Ds'—Diagnosis, Dental treatment, and Drugs
• Mild to Moderate Acute Dental Pain:
  • Ibuprofen $400$ mg orally every 6-8 hours (max 5 days) + Paracetamol $1000$ mg orally every 4-6 hours (max $4$ g/24 hours).
  • Or Celecoxib $100$ mg orally twice daily (max 5 days) + Paracetamol $1000$ mg orally every 4-6 hours (max $4$ g/24 hours).
  • If NSAIDs contraindicated: Paracetamol $1000$ mg orally every 4-6 hours (max $4$ g/24 hours).
• Severe Acute Dental Pain (if NSAIDs can be used):
  • Ibuprofen $400$ mg orally every 6-8 hours (max 5 days) + Paracetamol $1000$ mg orally every 4-6 hours (max $4$ g/24 hours) + Oxycodone immediate-release $5$ mg orally every 4-6 hours as needed (max 3 days).
  • Or Celecoxib $100$ mg orally twice daily (max 5 days) + Paracetamol $1000$ mg orally every 4-6 hours (max $4$ g/24 hours) + Oxycodone immediate-release $5$ mg orally every 4-6 hours as needed (max 3 days).
  • If NSAIDs cannot be used: Paracetamol + Oxycodone.
• Tapering analgesics: Stop oxycodone, then ibuprofen/celecoxib, then paracetamol.
• Post-operative pain in children:
  • Ibuprofen $5-10$ mg/kg orally every 6-8 hours (max $2400$ mg daily) OR Paracetamol $15$ mg/kg orally or rectally every 4-6 hours (max $4$ g daily).