Pain Flashcards
What pain is nociceptive pain?
MSK - NSAIDs
Dental pain - NSAIDs
Moderate to severe visceral pain - opioids
Period pain - oral contraceptives, antispasmodics, non-opioids
What is used for neuropathic pain?
TCAs - amitriptyline, nortriptyline
Antiepileptics - gabapentin, pregabalin
Nerve compression by tumour - dexamethasone
What is the pain ladder?
Non-opioids - +/- adjuvant
Weak opioids - +/- non-opioid or adjuvant
Strong opioids - +/- non-opioid or adjuvant
What are the adjuvants used with the pain ladder?
Neuropathic pain - amitriptyline, nortriptyline, gabapentin, pregabalin
Bone metastases - bisphosphonates, strontium ranelate
Nerve compression by tumour - dexamethasone
What is paracetamol used for?
Mild-moderate pain and fever
Preferred in elderly
What is the adult dose of paracetamol?
0.5-1g every 4-6 hours as required. Max. 4g/day
What is the cautionary labels of paracetamol?
Do not take more than 2 at any one time. Do not take more than 8 in 24 hours
Contains paracetamol. Do not take anything else containing paracetamol while taking this medicine. Talk to a doctor at once if you take too much of this medicine, even if you feel well
What does paracetamol overdose cause?
Liver damage
Greater risk if < 50kg
What is used to treat paracetamol poisoning?
Acetylcysteine
What are the overdose symptoms of paracetamol?
Nausea, vomiting, right subcostal pain/tenderness
What is aspirin used for?
Antiplatelet
Fever and pain
What is the dose of aspirin for ACS, TIA?
300mg dispersible tablets
What is the dose for secondary prevention of thrombotic arterial events?
75mg OD for life
What is the dose of aspirin for fever and pain?
300-900mg every 4-6 hours as required
Maximum 4g per day
What is the cautionary label for aspirin?
Take with or just after food or a meal
Contains aspirin. Do not take anything else containing aspirin while taking this medicine
What are the side effects of aspirin?
GI irritation
Tinnitus in high doses
What are the contraindications of aspirin?
< 16 years as causes Reye’s syndrome
Unless Kawasaki or as an antiplatelet
Salicylate or NSAID hypersensitivity
What are the interactions of aspirin?
Increased risk of bleeding - antiplatelet or anticoagulants e.g. warfarin
How do the opioids work?
Acts in various opioid receptors located in the brain, spinal cord and other nervous tissue to relieve pain
What are the weak opioids?
Codeine - CD5, injections = CD2
Dihydrocodeine - CD5
Meptazinol - POM
What are the moderate opioids?
Tramadol - CD3, exempt from safe custody
What are the strong opioids?
Morphine - CD2, oral solution 13/5 or less CD5 Oxycodone - CD2 Diamorphine - CD2 Buprenorphine - CD3 Fentanyl - CD2 Methadone - CD2 Hydromorphone - CD2
What are the other opioids and their uses?
Alfentanil - CD2 intraoperative analgesia Remifentanil - CD2 intraoperative Pethidine- CD2 labour Dipipanone - CD2 Papaveretum - CD2 Pentacozine - CD3 Sufentanil - CD2 Tapentadol - CD2 less nausea and vomiting
What is the rescue dose for breakthrough pain?
1/10 - 1/6 total daily dose every 2-4 hours as required
Immediate release preparations
What is used for an opioid overdose?
Naloxone
What are the symptoms of opioid overdose?
Coma
Pinpoint pupils
Respiratory depression
How does naloxone work?
Opioid receptor antagonist
Reverses respiratory depression
Can be supplied without prescription
What are the side effects of opioids?
Dry mouth Nausea and vomiting Constipation Sedation Reduced concentration and confusion Euphoria and hallucinations Dependence and tolerance Respiratory depression Hypogonadism Adrenal insufficiency Hyperalgesia
What is the mnemonic of opioid side effects?
MORPHINE
Miosis Out of it Respiratory depression Postural hypotension Hyperalgesia Infrequency Nausea and vomiting Euphoria
What are the contraindications of opioids?
Comatose patients
Risk of paralytic ileus
Respiratory depression
Head injury or raised intracranial pressure
What are the interactions of opioids that cause increased sedation?
Antidepressants Antihistamines Alcohol Z-drugs Antipsychotics Antiepileptics Benzodiazepines
What opioid interaction can cause CNS excitation or depression?
MAOIs
What are the cautionary labels for opioids?
This medicine may make you sleepy
If this happens do not drive or use tools or machines
Do not drink alcohol
What is oral morphine used for?
Severe pain in palliative care and coughs
What are the main side effects of morphine?
Causes most euphoria, nausea, vomiting
What is the dose of oral morphine?
Every 4 hours for immediate release
12-24 hourly MR
What is the maximum dose increments for oral morphine?
1/3 or 1/2 of total daily dose per 24 hours
What is the equivalent parenteral dose of oral morphine?
Half the oral dose