Drugs Used in Clinical Practice as a Paramedic - Essay Example

? Pharmacology Activity Foreachof the body systemslisteddescribe the consequence of activation of the parasympathetic and sympathetic nervous systems, then describe a clinical symptom or condition that as a paramedic you may observe in someone with a highly activatedPARASYMPATHETIC nervous system. (6 marks) Body System Parasympathetic Activation Sympathetic Activation Clinical Symptom / Condition e.g.Heart - Rate Decreased heart rate Increased heart rate Bradycardia Heart – Force of Contraction Decreases cardiac contraction Increases the force of contraction Cardio vascular disorders like distorted cardiac rhythm Pupil Constricts the iris muscles to allow little light to pass to the pupil (Shiota and Kalat, 2012, p. 87) Relaxes the muscles of the iris so that more light can reach the pupil for a clearer view (Shiota and Kalat, 2012, p. 87) Blurred images Lungs Constriction of airway smooth muscles Increased mucous glad secretion Increased vascular permeability Some causes vasodilation Increases mucociliary activities (Shiota and Kalat, 2012, p. 86) Increased mucus production Enhanced mucociliary clearance Blockage of the airway and dryness of the of the epithelium Stomach Stimulates secretion of digestive enzymes Stimulates peristalsis in the stomach Facilitate storage of body energy in the form of fats Stimulate the excretion of wastes (Shiota and Kalat, 2012, p. 86) Produce a tendency to vomit Vomiting of undigested food (2 marks) (2 marks) (2 marks) Activity 2 For each drug,identify ONE paramedic indication,then in the subsequent columns list the molecular target, target tissue, type of interaction (i.e. agonist / antagonist / allosteric modulator / inhibitor) and briefly explain how the interaction of the drugwith the molecular targetaccounts forthe observed therapeutic effect for theparamedic indication identified in the first column.(24 marks) Drug Paramedic Indication Molecular Target Target Tissue Type of interaction Mechanism of Therapeutic Effect e.g. Salbutamol Acute asthma ?2-adrenoreceptor Lungs Agonist Activation of ?2 adrenoceptors in the lung causes relaxation of the bronchiole smooth muscle, bronchodilation and increased airflow. Adrenaline Allergic reaction Alpha2, Beta and Beta 2 epinephrine Skin Antagonist When it is introduced o the body, it bind the alpha subunit of for GTP molecule and the G-protein breaks the beta particle from the gamma subunit and all the parts remain membrane bound (Foye, Lemke and Williams, 2008, p. 87). Fentanyl Sedation and acute pain Opioid receptors Central nervous systems Agonist It produces effects by binding the opioid receptors so that the patient stimulate the mind through the effects of the drug (Bryant and Knights, 2010, p. 123) Ondansetron Nausea and Vomiting 5-HT3 Peripheral and central nervous system Antagonist The drug influence the 5-HT3 receptors that reduces the action of the vagus nerve that causes vomiting in a patient Midazolam Sedation and Gamma receptors Central Nervous system Agonist It accomplishes its functions on the body by enhancing the action of inhibitory neurotransmitter gamma-amino butyric acid that produces a depressant effect on the individual who uses them. Ipratropium Severe life-threatening bronchospasm Beta Lungs Antagonist The drug is an antimuscarinic agent that promote bronchodilation by inhibiting chlorinergic bronchomotor tone (Lyons, 2011, p. 97) Adenosine Irregular purse rate beta Cardiac muscle Antagonist It influences the regular contraction and relaxation of cardiac muscles to achieve regular purse rate Naloxone Respiratory depression Beta Central nervous system Antagonist Naloxone competes for similar receptor sites with opiods so that it can reduce or reverse the effects of the opiods in the body of a person (Shiota and Kalat, 2012, p. 76) Aspirin Acute cardiogenic pulmonary oedema Beta molecules Blood Antagonist It reacts with the body in such a way that a person reacts the clot that help reduce clotting of blood enabling the free flow of blood (Lyons, 2011, p. 98) (4 marks) (4 marks) (4 Marks) (4 marks) (8 marks) Activity 3 In pharmacodynamics, a drug can be thought of as 'selective' when it shows preference for interaction with one molecular target, even though it may be faced with many molecular targets to choose from, and indeed, salbutamol can act as an agonist at all ? adrenergic receptors, but at therapeutic doses it 'selects' the ?2 adrenergic receptor subtype in preference to others. Considering the drugs used in your clinical practice as a paramedic: In the first column, list FOUR receptors from different classes,thenin the second column, list their endogenous agonist(s).(2 marks) In the third column give an example of ONE drug that is a clinically relevant SELECTIVE agonist OR antagonist for each of the receptors.(2 marks) Receptor Endogenous agonist Selective drug agonist or antagonist  Ligand-gated ion channels  Acetylcholine  Amlodipine  G-protein couple receptors  GABA  2- Hydroxysaclofen  Enzyme linked receptors  Angiotensin Converting Enzyme  Aspirin  Nuclear receptors  Spironolactone  Tamoxifen Activity 4 Antagonists at receptors for neurotransmitters or hormones are often used clinically. Use a diagram to explain how ?-adrenoceptors antagonists produce clinically useful effects. (2 marks) Before the introduction of ?-adrenoceptors antagonists, the receptors are in their inactive form where agonists can attach and cause a poor health condition to the body. This happens because there is no objection to the attachment of an antagonistic substance leaving the membrane vulnerable to agonists ( See Figure 1 below). However, when the ?-adrenoceptors antagonists are introduced, they occupy the position that ought to be occupied by the agonists to ensure that there are difficulties for them to attach and produce a bad health condition in the body of a patient in a situation. figure 1. In the action of the ?-adrenoceptors antagonists, it occupies the empty top part of the figure 1 above so that no agonist can attach itself into the body and therefore, there is no way the body will be have infection. This ensures that body cannot have cardio vascular infections (Williams and Wilkins, 2009, p. 65). Considering the actions of ?-adrenoceptors throughout the body, would it be the most appropriate treat uncomplicated hypertension in 68 year old patient with moderate asthma and renal impairment with atenolol, metoprolol or propranolol? Briefly explain the reasons for your decision. In congestive heart failure, the ?-adrenoceptors antagonists have been found to contribute to the positive recovery of patients. This has been made possible through the use of etenolol, metaprolol and propanolol which have contributed to increased protection against agonists that result cause heart failure or renal impairment and moderate asthma. In relation to the effects of adrenoceptors, they are important because they reinforce each other and could be useful in treating people at an advanced state (Gulini, 2000, p. 78). This is because even though they have deleterious effects, they support each other in supportive care as could be seen in the use of ?4 which may replace other receptors to ensure that they are functional. This makes them very applicable for aged patients who seek attention for their health in case they suffer from infections of asthma and renal failure (Gulini, 2000, p. 76). Bibliography Bryant, B. J. & Knights, K. M. (2010). Pharmacology for health professionals. Chatswood, N.S.W: Elsevier Australia. Foye, W. O., Lemke, T. L., & Williams, D. A. (2008). Foye's principles of medicinal chemistry. Philadelphia: Lippincott Williams & Wilkins. Gaskell, E. E., & In Rostron, C. (2013). Therapeutics and human physiology: How drugs work. Oxford, UK: Oxford University Press. Gulini, U. (2000). Receptor chemistry towards the third millennium: Proceedings of the 12th Camerino-Noordwijkerhout Symposium, Camerino, Italy, 5-9 September 1999. Amsterdam: Elsevier. Lyons, I. (2011). Biomedical science. Oxford: Wiley-Blackwell. Shiota, M. N., & Kalat, J. W. (2012). Emotion. Belmont, CA: Wadsworth, Cengage Learning. Williams, L. & Wilkins. (2009). Clinical pharmacology made incredibly easy!. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins. Read More