Pain killers
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Transcript of Pain killers
PAIN KILLERS
SUBJECT- PHARMACOLOGY SUBMITTED TO- DR. RAHUL PEDDAWAD SUBMISSION DATE- 25/09/2016 PRESENTED BY- MS. PAYAL BARIYA
F.Y PHARMA MBA
ROLL NO. – MBAPH016001
WHAT IS PAIN ? ? ?Subjective experienceHard to explainPain is a direct response to an untoward event associated with tissue damage such as Injury Inflammation Cancer, etc.
TYPES OF PAIN ACUTE trauma or injury, CHRONIC conditions for which cures were
unknown, MALIGNANT processes (cancer)
Based on etiology pain is differentiated into two types
1) NOCICEPTIVE PAIN
2) NEUROPATHIC PAIN
Nociceptive Pain:• Result of activation of sensory receptors
(nociceptors) by mechanical, chemical, or thermal stimuli.• Functional, physiologic or “normal” pain.Neuropathic Pain:• Pain resulting from damage to peripheral
nervous or central nervous system tissue or from altered processing of pain in the CNS.
HOW PAIN IS GENERATED ? ?
CONTD……
ANALGESIC DRUGS
PAIN KILLERS
OPIOIDSNSAIDS
OPIOIDS - OPIUMA dark brown, resinous material obtained from poppy plant (Papaver Somniferum; Family: Papaveraceae)capsule. It contains two types of alkaloids.
Phenanthrene derivatives
• Morphine• Codiene• Thebaine
Benzoisoquinoloine derivatives
• Papaverine• Noscapine
CLASSIFICATION OF OPIOIDS
• MORPHINE, CODIENE
NATURAL OPIUM ALKALOIDS
• DIACETYLMORPHINE(HEROIN), PHOLCODIENE
SEMISYNTHETIC OPIATES
• PETHIDINE, FENTANYL, METHADONE, DEXTROPROPOXYPHENE, TRAMADOL
SYNTHETIC OPIATES
MORPHINEMORPHINE IS THE PRINCIPLE ALKALOID IN OPIUM AND WIDELY USED ANALGESIC DRUG.
PHARMACOLOGICAL ACTIONS OF MORPHINE.
ON CNSANALGESIA:- Strong analgesic- High doses-severe pain- Intrathecal injection causes segmental analgesiaSEDATION:- Drowsiness - Inability to concentrate - Extravagant imagination- Larger doses produce sleep- EEG resembles normal sleep.
PHARMACOLOGICAL ACTIONS OF MORPHINE (CONTD.)
DEP
RES
SIO
N • Respiratory centre depression
• Cough centre• Temperature
regulating centre
• Vasomotor centre.
STIM
ULA
TIO
N • Vagal centre• Hippocampal
cells- convulsions (inhibition of GABA release).
Pharmacological actions of morphine contd.MOOD EFFECTS:- Normal person – calming effect, absence of pain- Dysphoria- In addicted persons- KICK- Euphoria NEURO-ENDOCRINE:- Hypothalamic activation is dampened- Hypothalamic influence on pituitary- Thus; FSH, LH and ACTH levels are lowered – only short
term- tolerance develops.- Decrease in levels of sex hormones and corticosteroids, but
no infertility; except in few cases.
PHARMACOLOGICAL ACTIONS OF MORPHINE. (CONTD.)
CVS:- Direct effect on heart- Vasodilation- histamine release, depression of
vasomotor centre.- Postural hypotension and fainting- Decreased cardiac output. GIT:- Constipation- reduced spasm of sphincters and GIT
secretions ANS:- Mild hyperglyceamia
MORPHINE PHARMACOKINETICS ABSORPTION:- Variable orally, IM or IV DISTRIBUTION:- Widely distributed – liver, kidney, spleen, etc.- Enters brain slowly- Crosses placental barrier- dependence in foetus METABOLISM:- In liver by glucoronidation-water soluble metabolites- Morphine-6-glucoronide –analgesic-renal failure-prolong analgesia- Morphine-3-glucoronide –no analgesia- neuroexcitatory. EXCRETION:- Action lasts for 4-6 Hrs- Completely eliminated in 24 Hrs.
MORPHINE- ADVERSE EFFECTSRespiratory depression-Infants and OldVomitingSedation: Mental cloudingHypotensive effectApnoea: newbornUrinary retentionIdiosyncrasy and allergyAcute morphine poisoningTolerance and dependence
MORPHINE – THERAPEUTIC USESANALGESIC1. Long bone fracture2. Myocardial infarction3. Terminal stages of cancer4. Burn5. Postoperative patients6. Biliary colic and renal colic7. Obstetric analgesia8. Segmental analgesia
MORPHINE – THERAPEUTIC USES (CONTD.)OTHERS1.Preanaesthetic medication2.Surgical analgesia3.Cardiac asthma4.Diarrhoea
PETHIDINEMORPHINE Vs PETHIDINE 1/10th as potent as morphine, but efficacy
is same. Same amount of sedation, euphoria and
respiratory depression Rapid but short DOA No antitussive action Safe margin in asthamic conditions Better oral absorption
PETHIDINE – CONTD.PHARMACOKINETICS: Well absorbed orally. Effect produced within 20 mins Parenteral administration- action lasts for 2-3
hrs Metabolized in liver-mepiridinic acid and
norpethidine Norpethidine accumulates on chronic use Excreted In urine
PETHIDINE – CONTD.ADVERSE EFFECTS: Similar to morphine Atropine like effects Overdose- tremors, mydriasis, convulsion
due to norpethidine accumulation.USES: Substitute for morphine Preanaesthetic medication Analgesic during labour- less foetal
respiratory depression.
METHADONE
Chemically dissimilar but pharmacologically similar Action is shown orally and parenterally DOA same as morphine Accumulation – repeated administration Highly bound to plasma proteins 80-90% Metabolized by liver Excreted in urine Abuse potential is low Substitution therapy – 1:4mg and 1:20mg of Morphine and
Pethidine resp. Codiene as a substitute in Methadone addiction.
TRAMADOLAnalgesicLow actionSpinal inhibition of painEffective both orally and by IV Side effects = morphine but less
prominentWell tolerated and low abuse
potential
REFERENCES:Essentials of Medical
Pharmaccology, KD TripathiRang and Dale’s
PharmacologyPharmacology, Vidyakumar
Padmaja