UNIT 3 Antiinflammatory and Autocoids.pdf

Diploma in Healthcare Please do not reproduce, redistribute or share without the prior express permission of the author. Introduction to Pharmacology 3 Anti-inflammatory and Autocoids Please do not reproduce, redistribute or share without the prior express permission of the author. 3.1 Anti Histamin...

Diploma in Healthcare Please do not reproduce, redistribute or share without the prior express permission of the author. Introduction to Pharmacology 3 Anti-inflammatory and Autocoids Please do not reproduce, redistribute or share without the prior express permission of the author. 3.1 Anti Histamine Please do not reproduce, redistribute or share without the prior express permission of the author. Topic/ Chapter Learning Outcome 1. Understand the role of histamine in inflammatory response or allergic reaction. 2. Identify types of histamine receptors. 3. Define and identify 2 types of anti-histamine. Please do not reproduce, redistribute or share without the prior express permission of the author. Histamine Histamine is a substance present in various tissues of the body (heart, lungs, gastric mucosa and skin). Highest concentration of histamine is found in basophil and mast cells near capillaries. Histamine is produced in response to injury. Also released in allergic or hypersensitivity reactions. Mast cell Basophil granulocytes Please do not reproduce, redistribute or share without the prior express permission of the author. Action of Histamine Tissues Injury Histamine released Act on vascular system and smooth muscle Dilation of arterioles Increase permeability of capillaries and venules Localized redness Escape of fluid from blood vessels into surrounding tissues Thus, release of histamine produces an inflammatory response Localized swelling Please do not reproduce, redistribute or share without the prior express permission of the author. Mechanism of action Histamine exerts its actions by combining with its receptors located on cells. There 4 histamine receptors found on cells. H1, H2, H3 and H4 receptors. H1 – found on smooth muscle and central nervous tissue. It causes vasodilation, broncho-constriction, smooth muscle activation, pain and itching due to insect sting. H2 – located on stomach cells which regulate gastric acid secretion. Please do not reproduce, redistribute or share without the prior express permission of the author. Anti-Histamine An antihistamine is a drug which reduce or eliminate effects mediated by histamine, through action at the histamine receptor. Mode of Action (MOA) BLOCKs action of histamine at the receptor sites. Compete with histamine for binding at unoccupied receptors. If histamine is already bound, antihistamines cannot remove histamine. Please do not reproduce, redistribute or share without the prior express permission of the author. Histamine vs. Anti-Histamine Histamine Effects on sites Anti-Histamine Dilation, increase permeability (fluid leak into tissues). Small blood vessels Prevent dilation, decrease permeability (fluid cannot enter tissues). Mast cells release histamine resulting in allergic reaction. Immune system Prevent histamine release, no allergic reaction. Stimulate salivary, gastric and bronchial secretions. Smooth muscle Prevent salivary, gastric and bronchial secretions. Please do not reproduce, redistribute or share without the prior express permission of the author. Types of Anti-Histamine H1 receptor antagonist 1st Generation H1-receptor antagonist 2nd Generation receptor antagonist H2- receptor antagonist Please do not reproduce, redistribute or share without the prior express permission of the author. 1st Generation H1-receptor antagonist Traditional and oldest anti-histamines. Cheaper and widely available. Work both peripherally and centrally. More effective (in some cases) Sedating anti-histamine (cause sleepiness) Examples: diphenhydramine, chlorpheniramine. (cough medication) Please do not reproduce, redistribute or share without the prior express permission of the author. 2nd Generation H1-receptor antagonist Nonsedating antihistamines. Does not cause sedation (sleepiness) Does not cross Blood Brain Barrier (BBB), fewer CNS side effects. Examples: loratadine (Claritin) (flu medication) oo Please do not reproduce, redistribute or share without the prior express permission of the author. H2- receptor antagonist Histamine H2-receptors are found principally in the stomach cells. H2-receptor "antagonists" are used to reduce the secretion of gastric acid. Examples: cimetidine, ranitidine, and famotidine Please do not reproduce, redistribute or share without the prior express permission of the author. Use of Anti-Histamine Allergic rhinitis Allergic dermatological condition Pruritis (insect bites) Relief of cough caused by colds or allergic Relief of nausea and vomiting Adjuncts to analgesic Please do not reproduce, redistribute or share without the prior express permission of the author. Adverse Reaction Drowsiness and sedation Dryness of mouth, nose and throat Thickening of bronchial secretion Photosensitivity Dizziness and headche Hypotension Fatigue Please do not reproduce, redistribute or share without the prior express permission of the author. 3.2 Pain Management Please do not reproduce, redistribute or share without the prior express permission of the author. Topic/ Chapter Learning Outcome 1. Review of sensory system. 2. Define Pain and types of Pain. 3. Define Analgesic and types of Analgesics. 4. Describe about Non-Opioid Analgesic and their effects. 5. Describe about Opioid Analgesic and their effects. 6. Describe about Co-Analgesic and their effects Please do not reproduce, redistribute or share without the prior express permission of the author. SENSORY SYSTEM Gather the information from external environment that allows the brain to make decision. Types of Senses: Touch Taste Sight Smell Hear Please do not reproduce, redistribute or share without the prior express permission of the author. SENSORY RECEPTORS Receptors are the actual structures that respond to our environment. Nociceptor – nerve receptors that transmits pain impulses Nociceptors are free nerve endings and stimulated by tissue damage. Widely distributed though out the skin and the tissues of internal organs, except brain. Please do not reproduce, redistribute or share without the prior express permission of the author. Please do not reproduce, redistribute or share without the prior express permission of the author. SENSORY PATHWAY If a receptor is stimulated enough, it results in an action potential. The action potential reaches the brain. The stronger the stimulus the greater number of action potentials reach the brain. The brain will interpret the action potential and sends message (response) to body parts. Please do not reproduce, redistribute or share without the prior express permission of the author. What is Pain? “An unpleasant sensory & emotional experience associated with actual or potential tissue damage”. One of the body’s defense mechanism (warns the brain that tissues may be in jeopardy) Please do not reproduce, redistribute or share without the prior express permission of the author. Types of Pain Somatic pain Pain in skin and muscular tissue. Deep Somatic Pain – stems from tendons, muscles, joints, periosteum, & blood vessels. Visceral Pain Pain from internal organs. Neuropathic pain Pain in the nerve pathways. Please do not reproduce, redistribute or share without the prior express permission of the author. Mechanism of Pain A receptor must detect the stimulus and create an impulse. The impulse must be conducted to the central nervous system. Within the CNS, the impulse must be translated into information. Information must be interpreted in the CNS into an awareness or perception of the stimulus. Please do not reproduce, redistribute or share without the prior express permission of the author. Please do not reproduce, redistribute or share without the prior express permission of the author. Goal of Pain Management Reduce pain Control acute pain Protect the patient from further injury while encouraging progressive exercise. Please do not reproduce, redistribute or share without the prior express permission of the author. Analgesics An analgesic is known as a painkiller. It is any member of the diverse group of drugs used to relieve pain and to achieve analgesia (without pain). Analgesic drugs act in various ways on the peripheral and central nervous system. Please do not reproduce, redistribute or share without the prior express permission of the author. Types of Analgesics Drugs used in pain management can be divided into: Non-opioid Analgesic Opioid Analgesic Co-Analgesics Please do not reproduce, redistribute or share without the prior express permission of the author. Non-Opioid Analgesics Drugs that relieve pain without the causing addiction. The non-opioid analgesics can be divided into 3 groups: Salicylates (Aspirin) Non-salicylates (Acetaminophen – Panadol) Non-steroidal Anti-Inflammatory Drugs – NSAIDs (Ibuprofen) These drugs can be obtained without prescription Please do not reproduce, redistribute or share without the prior express permission of the author. Mode of Action MOA: Act by inhibiting synthesis of prostaglandins (molecules involved in the peripheral perception of pain). Therapeutic Uses To relief mild to moderate pain Reduce elevated body temperature Treatment of inflammatory condition (except acetaminophen). Please do not reproduce, redistribute or share without the prior express permission of the author. Adverse Reactions Gastric upset & heartburn Nausea & vomiting Gastrointestinal bleeding Jaundice & hepatotoxicity. Constipation Hypertension & dizziness Photophobia. Please do not reproduce, redistribute or share without the prior express permission of the author. Opioid Analgesics Opioid analgesics are obtained from the plant opium poppy. Most powerful pain-relieving agents Also used just before or during an operation to help the anesthetic works better. Must be prescribed by doctor. Please do not reproduce, redistribute or share without the prior express permission of the author. Mode of Action MOA : Opioid analgesics act on brain receptors (CNS) to inhibit sensory impulses especially pain. Carry a risk of drug addiction. Therapeutic Uses To relieve pain To sedate the patient Support of anesthesia Please do not reproduce, redistribute or share without the prior express permission of the author. Adverse Reactions Weakness Insomnia Tremor Dry mouth Allergic Physical dependency Please do not reproduce, redistribute or share without the prior express permission of the author. Please do not reproduce, redistribute or share without the prior express permission of the author. Co- Analgesics A drug used to enhance pain relief. Increase the effect of opiods or NSAIDs. Not normally considered analgesics Examples of Co-Analgesics Tricyclic antidepressants Muscle Tone Modulator Local anesthetic Please do not reproduce, redistribute or share without the prior express permission of the author. REFERENCE Holland, LM and Adams MP. 2007. Core Concepts in Pharmacology. 2nd edition.Pearson. Hitner H and Nagle B. 2002. Basic Pharmacology. 4th edition. McGraw-Hill. Please do not reproduce, redistribute or share without the prior express permission of the author. Next Topic Drugs that affect the respiratory system Please do not reproduce, redistribute or share without the prior express permission of the author. Thank you Address Lot 33-40, Blok C, Plaza Juta, KM 7.2 Off Jalan Tuaran, 88400 Likas, Kota Kinabalu, Sabah, Malaysia Telephone +6088 431 025/35 Website kk.cyberjaya.edu.my Email [email protected] Please do not reproduce, redistribute or share without the prior express permission of the author.