Analgesics Flashcards
What different analgesic medications are there?
- Paracetamol
- NSAID
- Opioids Agonist
- Opioid Antagonist
- Synthetic Opioid
What are the 4 steps of the pain pathway?
- Transduction
- Inflammatory mediaters are released and activate
the first neuron , sends message for pain
- Inflammatory mediaters are released and activate
- Transmission
- Neurons are firing (A delta fast, C slow)
- Perception of pain
- Modulation
- Alters a pain signal as it is transmitted along the pain pathway
How many opioid receptors are there and what are they called?
Mu
Kappa
Delta
What is an example of an opioid agonist?
Morphine
Loperamide
Codeine
What is the indication of use for opioid medications, specifically Morphine?
Typically, Opioids are prescribed for the short-term treatment of moderately severe or severe pain, such as pain experienced following surgery or an injury. They can be prescribed for palliative care and chronic pain.
What is the MOA for opioid medications?
Spinal level: stimulates opioid receptor and inhibits substance p release from the dorsal horn neurons.
Supraspinal: closes dorsal horn gate inhibiting afferent transmission to cortex. Alter pain perception and response.
Stimulates mu receptors
What are some adverse drug reactions associated with Opioid medications?
Respiratory depression, Excessive sedation, Dysphoria, Constipation, Nausea & vomiting, Tolerance and Dependence, (histamine release) itch, bronchoconstriction, urinary retention, Euphoria
What patient education would you provide to someone who is on opioid medications?
- Do not drink alcohol
- This medication may be addictive with prolonged use, talk to Dr. if you feel it isn’t working for you anymore
- Has sedation effects and may make you more sleepy than normal
- This medication can make you constipated
What are some cautions/contraindications associated with opioids?
Interacts with alcohol, Monoamine oxidase inhibitor. Opioid antagonist. Avoid in head injury
What are the KEY monitoring requirement associated with opioids?
Bowels
Resp rate
Sedation
Nausea/Vomiting (input/output)
What slow releasing types of morphine are available?
m-Elson capsules, LA Morph tablets
What are some immediate releasing type of morphine which are available?
Severdol tablets or RA Morph solution
What must be available for IV morphine administration?
Naloxone and oxygen
How do morphine infusions occur? and what monitoring requirements are required?
Through a pump. Monitoring of respiratory rate as well as sedation recorded hourly throughout the infusion as can cause respiratory depression and sedation.
What is the indication of use for Loperamide?
Acute and chronic diarrhoea
What is the MOA for Loperamide?
Loperamide is synthetic opioid that binds to the opiate receptor in the gut wall. Consequently, it inhibits the release of acetylcholine and prostaglandins, thereby reducing propulsive peristalsis, and increasing intestinal transit time. Loperamide increases the tone of the anal sphincter, thereby reducing incontinence and urgency. Slows down the movement of the gut
What are some adverse drug reactions associated with Loperamide?
Nausea, abdominal cramps, dizziness, drowsiness, urticaria (a raised, itchy rash that appears on the skin)
What are some contraindications/cautions associated with Loperamide?
Conditions where inhibition of peristalsis should be avoided; where abdominal distension develops or in conditions such as active ulcerative colitis or antibiotic-associated colitis. Ensure appropriate use of fluid and electrolyte replacement; in acute diarrhoea only use for short-term symptomatic management
What patient education would you provide to someone on Loperamide?
- Loperamide can be taken before or after food.
- If you forget to take a dose, just take a dose after the next time you go to the toilet with diarrhoea. Do not take two doses together to make up for a missed dose.
- Make sure you drink plenty of water or electrolyte replacement drinks because diarrhoea can make you dehydrated.
What opioid antagonist can reverse opioid overdose?
Naloxone
What is the MOA for Naloxone?
Attach to opioid receptor within the nervous system but not stimulate them = prevention of opioid effects.
What are some adverse drug reactions associated with Naloxone?
Nausea, vomiting, hypotension, hypertension, tachycardia, headache, dizziness, dry mouth
What is an example of a Synthetic Opioid?
Tramadol
What is the indication of use for Tramadol?
Moderate to severe pain; post-operative pain