F. Clinical use of analgesic II: opioids and other medicines Flashcards
What are the three types of opioids?
Naturally occurring
Semi-synthetic
Synthetic
Give an example of a naturally occurring opioid
Morphine
Codeine
Thebaine
Papaverine
Give an example of a semi-synthetic opioid
Oxycodone
Diamorphine (heroin)
Buprenorphine
Hydromorphone
Give an example of synthetic opioids
Tramadol
Pethidine
Fentanyl
Alfenranil
What receptor provides analgesic and side effects associated with opioids
Meu (MOR)
What opioids are used to treat moderate pain (weak opioids)
Codeine
Dihydrocodiene
Dextropropoxyphene
What opioids are used to treat severe pain (strong opioids )
Morphine Dimorphine Oxycodone Fentanyl Tramadol
What pain comes under severe pain?
Acute pain
Persistent non cancer pain (low back pain, osteoarthritis)
Palliative pain
What are the routes of administration for opioids ?
Oral Rectal Transdermal Sublingual Topical Intramuscular Subcutaneous Intravenous Epidural Intrathecal
What are the common side effects for opioid use ?
Nausea and vomiting Constipation Sedation Respiratory depression Hypotension Urinary retention
What are the less common side effects with opioids ?
Narcotic bowel syndrome
Immunosuppressant
Endocrine dysfunction
Addiction
What non pharmacological treatments can be provided to patients suffering from opioid induced constipation?
Diet (fruits and fibre)
Fluids
What laxatives can be provided to patients with opioid induced constipation?
Stimulants in combination with stool softeners (Docusate or bisacodyl)
What peripherally restricted opioid antagonist can be administered ?
Doesnt get to the central nervous system and doesnt effect the analgesic effect
Methyltrexone
Naloxone
Naloxegrol
How would you initiate oral morphine for pain?
- Give a pain assessment, including current analgesia
- Determine opioid requirement
- calculate 24hr requirement
- Convert to modified release formulation eg MST, zomorph
How would you initiate oral morphine for pain?
- Give a pain assessment, including current analgesia
- Determine opioid requirement
- Calculate 24hr requirement
- Convert to modified release formulation eg MST, zomorph
What are the advantages of PCA?
Rapid analgesia once pain at steady state
Ready preparation
Patient satisfaction
No dose delay
Pain acceptability
No peaks or troughs
What are the disadvantages of PCA?
Expensive
Requires IV access
Training
Monitoring
What is the drug of choice for PCA ?
Morphine
What is the drug of choice if patient is allergic to morphine?
tramadol, oxycodone or fentanyl
What does an epidural opioid contain?
Mixture of local anaesthetic and opioid
Such as fentanyl with bupivicaine (or levobupicacaine )
Why is fentanyl less likely to cause respiratory depression ?
It has a high lipophilicity therefore cannot cross the bbb
What are the adverse effects of epidural opioids ?
Hypotension
Wrong route
Infection
Haemotoma (bad bruise)
When can continuous subcutaneous infusions be used ?
- unable to take medicine by mouth
- bowel obstruction
- patients does not wish to take regular medication by mouth
