Analgesics commonly used in dentistry India

presentation involves analgesics in detail

1. Analgesics Pain is inevitable suffering is optional Arulvignesh M MAXFAC PG 1 ST YEAR ORALANDMAXILLOFACIALSURGERY

2. PAIN An ill-defined, unplesant sensation, usually evoked by a noxious stimulant. Its a warning or signal and primarily protective in nature, but causes discomfort and suffering.

3. The  Penfield Homunculus : Depicts disproportionately large areas dedicated to the face and jaw regions

4. to understand the ratios between the different body regions' levels of motor or sensory innervation The sensorimotor homunculi

5. Analgesic Analgesic , any  drug  that relieves  pain  selectively without blocking the conduction of nerve impulses, markedly altering sensory perception, or affecting consciousness. Anesthesia , on the other hand, is the loss of physical sensation with or without loss of consciousness using anesthetics (e.g., Ketamine , Propofol , Isoflurane , etc.)..

6. Subjective pain

7. Objective pain  – Clinical features of pain include tachycardia, tachypnoea , hypertension, sweating, or flushing An unwillingness to mobilise or agitation may be present in those that are less able to communicate their pain

8. Pre-Emptive Analgesia Pre-emptive analgesia is defined as an antinociceptive treatment that is started preoperatively and is active during surgery, reducing the physiological consequences of nociceptive transmission

9. Post operative analgesia

10. Types Analgesics may be classified into two types: Anti-inflammatory drugs, which  alleviate  pain by reducing local inflammatory responses Opioids , which act on the  brain . The opioid analgesics were once called  narcotic  drugs because they can induce  sleep .

11. NSAIDS

12. Asprin One of the oldest Analgesic anti-inflammatory drugs and is frequently used. Aspirin inhibits COX irreversibly by acetylating one of its serine residues ; Return of COX activity depends on synthesis of fresh enzyme.

13. Uses As analgesic : For headache, backache, myalgia, joint pain pulled muscle, toothache, neuralgias, dysmenorrhoea Effective in low doses [ 0.3-0.6 g 6-8 hourly] Maximal effect is 1000 mg As antipyretic - thermostat ? Post MI and post stroke patients

14. Aspirin (ASA) is a non-steroidal anti-inflammatory drug with selective anti-platelet activity, Aspirin also significantly reduces the incidences of post-operative myocardial re-infarction , cerebrovascular events and other thrombotic pathology However, inhibiting platelets can potentially increase the amount of post-operative bleeding and there have been a number of studies to suggest the fact. Does Early Post-operative Administration of Aspirin Influence the Risk of Bleeding After Coronary Artery Bypass Graft Surgery? A Prospective Observational Study Seyed Mahmood Nouraei , 1   Afshin Gholipour Baradari , 2  and  Amir Emami Zeydi 3

15. Preparations ASPIRIN 350 mg tab COLSPIRIN 100,325, 650 mg tab ECOSPIRIN 75 , 150 , 325 mg tabs DISPIRIN 350 mg tab LOPRIN 75,162.5 mg tabs An injectable preparation has also been made available. BIOSPIRIN : Lysine acetylsalicylate 900 mg + Glycine 100 mg/ vial for dissolving in 5 ml water and IV injection

16. Manifestations are :- Vomiting , Dehydration , Electrolyte imbalance , Acidotic breathing Hyper/hypoglycaemia , Petechial haemorrhages , Restlessness , Delirium , Hallucinations , Hyperpyrexia , Convulsions, Coma and Death due to respiratory failure +Cardiovascular collapse.

17. Contra indications peptic ulcer bleeding tendencies Due to risk of Reye’s syndrome , pediatric formulations of aspirin are prohibited in India and the UK chronic liver disease: cases of hepatic necrosis have been reported.

18. Aspirin should be stopped 1 week before elective surgery, dental extraction. Given during pregnancy, it may be responsible for low birth weight babies. It should be avoided by breastfeeding mothers. Avoid high doses in G-6-PD deficient individuals— haemolysis can occur.

19. In case this is not possible, adequate haemostasis must be ensured by packing the socket and use of local haemostatics if needed. Delayed or prolonged labour , greater postpartum blood loss and premature closure of ductus arteriosus are possible if aspirin is taken at or near term.

20. 2.Ibuprofen It has been rated as the safest traditional NSAID by the spontaneous Ibuprofen (400 mg) has been found equally or more efficacious than a combination of aspirin (650 mg) + codeine (60 mg) in relieving dental surgery pain

21. USES Ibuprofen and its congeners are widely used in rheumatoid arthritis, osteoarthritis,and other musculoskeletal disorders, especially where pain is more prominent than inflammation. They are indicated in soft tissue injuries, tooth extraction, fractures, vasectomy, postpartum and postoperatively Control of postsurgical pain. Most common prescription Peak blood levels obtained within 1-2 hours , stays active as an analgesic for 4 to 6 hours .

22. Naproxen Dose – 750 mg stat followed by 250 mg 8 hourly till pain subsides Indicated for RA, ankylosing spondylitis , osteoarthritis, primary dysmenorrhea, acute gout GI adverse effects with less severity CNS side effects such as drowsiness, headache, dizziness Pharmacological basis of therapeutics by Goodman and Gilman

23. Diclofenac sodium Inhibits PG synthesis, COX-2 selective Short lasting anti-platelet action, Neutrophil chemotaxis reduced, Superoxide production at inflammatory site reduced THERAPEUTIC USES Efficacy similar to naproxen Effective Postoperative dental surgery pain reduction Severely painful conditions: -Acute periapical and periodontal abscesses Dose: 50mg 2-3 times/ day

24. Piroxicam Long acting potent NSAID Chemotaxis of leukocytes reduced 99% of drug is absorbed Inhibits platelet aggregation – prolongs bleeding time THERAPEUTIC USES As short term analgesic and long term anti-inflammatory drug RA, OA, Ankylosing spondylitis , gout. Postoperative and post trauma pain, Dental and minor surgical pain

25. Ketorolac A novel NSAID with potent analgesic and modest antiinflammatory activity. In postoperative pain it has equalled the efficacy of morphine Plasma t1/2: 5-7 hours Adverse effects : Rise in serum transaminase, fluid retention, pain at inj.site Nausea, abdominal pain, dyspepsia, ulceration, loose stools, drowsiness, headache, dizziness

26. Uses Ketorolac is frequently used in postoperative, dental and acute musculoskeletal pain: 15– 30 mg i.m. or i.v. It can also be used for migraine and pain due to bony metastasis . Orally it is used in a dose of 10–20 mg 6 hourly for short-term management of moderate pain. In postoperative dental pain ketorolac has been rated superior to aspirin 650 mg, paracetamol 600 mg and equivalent to ibuprofen 400 mg.

27. Paracetamol/Acetaminophen When aspirin should be avoided, acetaminophen is an excellent substitute. Analgesic- antipyretics with poor -Anti -inflammatory action equals aspirin in analgesic and antipyretic potency. does not have the adverse gastrointestinal effects or the antiprothrombin and antiplatelet effects of aspirin. ANALGESIC- ANTIPYRETICS WITH POOR ANTI -INFLAMMATORY ACTION

28. Acute paracetamol poisoning It occurs specially in small children who have low hepatic glucuronide conjugating ability. If a large dose (> 150 mg/kg or > 10 g in an adult ) is taken, serious toxicity can occur. Fatality is common with > 250 mg/kg. Early manifestations are just nausea, vomiting, abdominal pain and liver tenderness with no impairment of consciousness. After 12–18 hours centrilobular hepatic necrosis occurs Accompanied by renal tubular necrosis and hypoglycaemia that may progress to coma. Jaundice starts after 2 days.

29. Dental indications of paracetamol Control of postsurgical pain. Peak blood levels obtained within 30 minutes to one hour, stays active as an analgesic for four to six hours. Adults 500 to 1000 mg acetaminophen every four to six hours. Do not exceed 4000 mg per day. It can be used in pregnancy and during nursing. Usually given in combination with Ibuprofen Chronic pulpitis, Periodontal abscess, Post-extraction

30. Dose: 0.5–1 g TDS; infants 50 mg; children 1–3 years 80– 160 mg, 4–8 years 240–320 mg, 9–12 years 300–600 mg. CROCIN 0.5, 1.0 g tabs; METACIN, PARACIN 500 mg tab, 125 mg/5 ml syrup, 150 mg/ml paed . drops, ULTRAGIN, PYRIGESIC, CALPOL 500 mg tab, 125 mg/ 5ml syrup, NEOMOL, FEVASTIN, FEBRINIL 300 mg/2 ml inj. CROCIN PAIN RELIEF: Paracetamol 650 mg + Caffeine 50 mg tab

31. Adverse effects, preparations and dosage In isolated antipyretic doses paracetamol is safe and well tolerated. Nausea and rashes occur occasionally, leukopenia is rare. Kidney damage and liver damage occurs in overdosage

32. GIT risk of NSAID’s The risk for gastrointestinal complications increases in the following patient groups necessitating prudent drug choice in : patients above the age of 65 years. patients with a history of previous peptic ulcer disease. patients taking corticosteroids / ASPRIN / anticoagulants. Chronic use, should not exceed 10 days for analgesia Alcohol consumption doubles the risk of g.i.bleeding

33. Use of anti-ulcer co-therapy Proton pump inhibitor( omeprazole ) Histamine h2-blockers( ranitidine,cimetidine ) and Antacids Prophylactic use of proton pump inhibitors in patients with previous gastrointestinal events or in those at high risk for such events is considered appropriate by major treatment guidelines

34. OPIOIDS

35. OPIOID ANALGESICS

36. OPIOID RECEPTOR ACTIVATION REDUCTION IN INTRACELLULAR cAMP [cyclic AMP] OPENS K + CHANNELS( μ,δ ) OR SUPPRESSES VOLTAGE GATED Ca 2+ CHANNELS( κ ) NEURONAL HYPERPOLARIZATION AND REDUCED AVAILABILITY OF INTRACELLULAR Ca 2+ DECREASED NUROTRANSMITTER RELEASE BY BRAIN, SPINAL CORD AND MYENTERIC PLEXUS MECHANISM OF ACTION

37. MORPHINE CNS ACTIONS DEPRESSANT ACTIONS Analgesia Sedation Mood and subjective effects Respiratory centre Cough centre Temperature regulating centre Vasomotor centre

38. ADVERSE EFFECTS Sedation, lethargy, mental clouding Vomiting Respiratory depression, blurring vision, urinary retention Urticaria , itch, swelling of lips High degree of tolerance and cross tolerance seen Abstinence- lacrimation, sweating, anxiety, fear, tremor, insomnia,etc . Treatment- Withdrawal of morphine with oral methadone + gradual methadone withdrawal.

39. ACUTE MORPHINE POISONING 50 mg Morphine I.M.- Serious toxicity Coma, shallow breathing, cyanosis, fall in BP, shock, convulsions Treatment Respiratory support, Bp maintainance with IV fluids, vasoconstrictors Gastric lavage with potassium permanganate Naloxone(0.4-0.8mg I.V.) repeated every 2-3mins till respiration picks up Injection to be repeated every 1-4hrs. NORMAL DOSAGE 10-50 mg oral, 10-15 mg IM or SC or 2-6 mg IV; children 0.1-0.2 mg/kg IM or SC.

40. CONTRA INDICATIONS Infants and elderly Respiratory insufficiency cases Bronchial asthma Head injury Hypotensive states Hypothyroidism Unstable personalities Phenothiazines and Tricyclic antidepressants- retard morphine metabolism

41. CODEINE Methyl-morphine Less potent(1/10 th as analgesic), less efficacious More selective cough suppressant Oral dose acts for 4-6hrs Constipation is prominent- used to control diarrhoea Abuse liability is low

42. HEROIN Diacetylmorphine 3 times more potent than morphine More lipid soluble More euphoriant (especially in IV) Duration of action similar to morphine Highly addicting No therapeutic advantage Even banned in some countries

43. FENTANYL 80-100 times more potent than morphine Few CVS effects, little histamine release Enters brain rapidly Peak analgesia in 5 mins after IV inj. Starts to wear after 30-40 mins. T1/2= 4hrs Transdermal fentanyl- cancer and chronic pain patient (25,50,75,100μg/hr. patch changed after every 2-3 days)

44. TRAMADOL Good oral bioavailability Maximum dose: 400 mg per day T1/2= 3-4hrs, effects last for 4-6hrs   naloxone   (a medicine to reverse an opioid overdose) Less respiratory depression, sedation, constipation, urinary retention Affinity for μ- moderate; κ,δ - weak

45. Well tolerated, low abuse potential Side effects- dizziness, nausea, sleepiness, dry mouth, sweating Indication- mild-medium intensity short lasting pain and chronic pain like in cancer but not in severe pain Dose- 50-100mg oral/IM/slow IV infusion 4-6 hourly.

46. The  World Health Organisation Analgesic Ladder   Best-known method for approaching pain relief. Strategy for  titrating analgesia , starting with simple analgesics and working  upwards to strong opioids Initially starting with  simple analgesics  (such as paracetamol or NSAIDs), if the pain is not well controlled, move up to the next stage of the ladder and consider prescribing  weak opiates , such as codeine or tramadol . Again, assess the response and if this is still inadequate, move to the next step and prescribe morphine or other  strong opiates .

47. WHO Analgesic Ladder

48. Consider  alternatives to the oral route , such as topical, intravenous, or subcutaneous. If this fails and sinister causes of pain have been ruled out, consider specialist help and/or a patient-controlled analgesia pump. Any  neuropathic pain  may respond better to alternative analgesics (see appendix), such as amitriptyline or gabapentin . ‘It is important to move down the ladder, and  wean down   the   analgesia’

49. The medications chosen were based on the 3-step ladder approach developed by the World Health Organization (WHO) in 1986 which emphasizes the importance of 3 principles: “by the clock, by the mouth, by the ladder”.

50. Thankyou !!!