L8 Opoid Flashcards
are drugs of choice for severe pain (MI) and chronic malignant pain?
Opioids
Natural or synthetic compounds that produce morphine like actions. ?
Opioids
Drugs that are obtained from the juice of opium poppy?
Opiates
Classifications of Opioid based on their actions?
Agonists:
-Strong agonists ( Morphine, Fentanil, Heroin)
-Moderate agonists (Codeine, Prophoxiphene )
-Agonist-antagonists ( Pentazocine, Nalbuphine)
-Partial agonist (Buprenorphine)
-Tramadol
Endogenous peptides related to opioid drugs?
Eendorphins, Enkephalins & Dynorphins
Three types of main opioid receptors:
• Mu
• Kappa
• Delta
Mechanism of action Opioids ?
act by interacting with opioids receptors in CNS, GIT & U.blader. They cause hyperpolarization of the nerve cells, inhibit nerves firing presynoptic release of transmitters like substance P
Actions of morphine?
-Miosis, Pinpoint pupil characteristic of morphine
-bronchoconstriction. So asthmatic patient should not use
-Inhibits release of sex hormone, may cause sexual problems
-delay 2 nd stage of labor due to decrease in strengh & frequency of contraction.
Uses of morphine ??
Main use: to alleviate moderate to severe pain like MI.
-Relief of Cough ( codeine or dextromethorphan)
-Diarrhea (Loperamide)
– Acute pulmonary edema(Morphine)
– Neurolept analgesia (Fentanyl)
used for acute pain. It does not cause pinpoint pupil, rather dilate it because of its atropine like action?
Meperidine
(………………). Used in neurolept analgesia
(…………….) Regional anesthesia; epidural or sub-arachnoid
Fentanyl
Morphine
acts as agonist on K receptors & weakly block Mu ?
Penazocine
Adverse effects of morphine?
Meiosis (pinpoint pupil)
Increased intracranial pressure
Constipation
Urinary retention
Decrease uterine tone and delay 2ed stage labor ( inc. 2ed stage )
Orthostatic hypotension
Opioids Antagonists?
Naloxone
naltrexone
Nalmefene
Contraindications of opioid :
• Acute respiratory depression, raised intracranial pressure, head injury, coma
