ANALGESICS Flashcards
What is an analgesic?
A drug which relieves pain of any origin.
Classify analgesics.
- Opoidal / Narcotic analgesic
- Non opoidal / Non-narcotic analgesic
Name examples of opoidal/narcotic analgesics.
- Morphine
- Pethidine
- Tramadol
- Fentanyl
- Pentazosine
- Methadone
Name examples of non opoidal/non-narcotic analgesics.( These are NSAIDS)
- Paracetamol
- Diclofenac
- Ketorolac
- Aceclofenac
- Aspirin
- Indomethacin
- Ibuprofen
- Naproxen
- Tenoxicam
Fill in the blank: An analgesic that relieves pain without the use of narcotics is called a _______.
Non opoidal / Non-narcotic analgesic
True or False: Morphine is classified as a non opoidal analgesic.
False
What type of analgesic is Fentanyl?
Opoidal / Narcotic analgesic
Fill in the blank: _______ is a common non opoidal analgesic used to relieve pain and reduce fever.
Paracetamol
What are the natural opoidal analgesics?
Morphine, Codeine, Endorphine, Dynorphine, Enkephaline
What are the semi-synthetic opoidal analgesics?
Diamorphine (Heroin), Dihydrocodeine, Hydrocodeine, Oxycodeine, Oxymorphine
What are the synthetic opoidal analgesics?
Pethidine, Fentanyl, Pentazosine, Loperamide, Nalbuphine
Which opoidal analgesics have high efficacy?
Morphine, Pethidine, Fentanyl, Tramadol, Diamorphine
Which opoidal analgesics have low efficacy?
Codeine, Dihydrocodeine, Pentazocine, Nalbuphine
Properties of narcotic/opoidal analgesics
•act in CNS
•Cause CNS depression
•Active in visceral pain
•Highly potent analgesics
•no antiinflammatory and antipyretic action
•used in labour pain (pethidine)
•low TI
•Chance of addiction, dependence
Pharmacological action of morphine
> CNS effects:
Analgesia
Sedation
Cough suppression
Respiratory distress
Nausea and vomiting
Miosis
Euphoria
Hyperthermia
Peripheral effects:
Bradycardia
Constipation
Increase billiary pressure
Urinary retention
Oliguria
Prolonged labour
Warming and itching of skin
Galactorhoea
Clinical use of morphine
•diagnosed severe visceral pain
>Pancreatitis, pericarditis, pleurisy, cholecystitis, pyelonephritis
•Post operative pain
•cancer pain
•burn pain
•MI
•Acute ALVF
•cough suppression
•spinal anaesthesia
Adverse effect of morphine
Nausea
Vomiting
Shivering
Warming
Itching
Sedation
Respiratory distress
Cough suppression
Miosis
Constipation
Urinary retention
Oliguria
Hypotension
Bradycardia
Euphoria
Dependence
Addiction liability
Contraindications of morphine and why
Undiagnosed acute abdomen
Bronchial asthma
Pregnancy
Head injury
Convulsive disorder
Biliary colic
Acute renal failure
Analgesic action of morphine
Morphine
Presynaptic nerve terminal
1.bind with opoidal reception
2.closing of Ca+² channel and release of glutamate, ach, noradrenaline, substance P
Post synaptic nerve terminal
1. Opening of potassium channel
2. increase Potassium channel
3. Hyperpolarization
4. Blocks pain pathway
Analgesic action
Morphine vs pethidine
Morphine
Natural
More potent
Duration 4-6 hrs pethidine 2-3
Miosis
Not used in pregnancy
Atropine effects
Tolerance develops quickly
Addiction more likely
