1. Drugs for pain!!! Miss Katy Davidson, BSc (Hons) Jason

2. WHO Pain ladder

3. Paracetamol  The exact mechanism of action for Paracetamol is unknown, although it is thought to selectively inhibit COX-2.  Used in mild pain relief and has a mild antipyretic effect.  What happens in a paracetamol overdose?

4. Overdose

5. NSAIDs  COX-1 and COX-2 Inhibitors. Inhibits the synthesis of prostaglandins and thromboxanes.  There are several different classes of NSAIDs, but they may not be worth learning…  Examples include: Ibuprofen, aspirin, diclofenac, naproxen

6. Complications  Action on COX-2 gives your anti-inflammatory, antipyretic and analgesic effects  Action on COX-1 gives you problems…  Inhibition of COX-1 reduces synthesis of PGE2 in the stomach which in turn increases the amount of acid secretion and decreases the amount of bicarbonate secretion.  How can this be countered?  Omeprazole and taking NSAIDs with food, care to be taken when prescribing to patients with heartburn/previous gastroduodenal ulcers

7. COX-2 selective Supposed to have fewer side effects as they do not target COX-1 Examples include: Celecoxib Etoricoxib This is all you really need to know

8. Mild opioids  Codeine  Dihydrocodeine  C0-codamol  Used for moderate pain upward  Broadly work on the mu, kappa and delta opioid type receptors  Common side effects?  Likely to cause constipation, especially in the elderly, at high doses or with long term use  How is this countered?  Avoid long term use if possible and co-prescribe laxatives in high risk patients.

9. Strong opioids  Morphine  Diamorphine  Tramadol  Used in severe pain  Can be highly addictive  Often cause problems with overdose

10. Opioid overdose  Symptoms?  Pin-point pupils (possibly), respiratory depression, tachycardia, hypotension, nausea/vomiting  How do you treat it?  Give IV naloxone, an opioid receptor antagonist  Occasionally Naltrexone may be given (longer acting)

11. Partial/mixed opioids Opioid addiction  Buprenorphine – Also used in opioid addiction alongside methadone  Pentazocine  Need to be aware of them

12. Neuropathic pain  First line is normally TCAs i.e. amitriptyline/nortryptyline or duloxetine (SNRI)  Second line is both of these combined  Third line is gabapentin/pregablin  Carbamazepine is often used in the treatment of trigeminal neuralgia

13. The end  Get out