If a single receptor type is responsible for regulating several physiologic

If a single receptor type is responsible for

This preview shows page 20 - 22 out of 24 pages.

If a single receptor type is responsible for regulating several physiologic processes, then drugs that interact with that receptor will also influence several processes. think also agonists and partial and antagonist Opioid receptors modulate perception of pain as well help regulate other processes including respiration and motility of the bowel o Morphine can also produce respiratory depression and constipation 20. Differentiate drugs that are Agonists: o molecules that activate receptors and mimic the body’s own regulatory molecules o neurotransmitters, hormones etc… o they can make a process go faster or slower partial agonists: o mimic the actions of endogenous regulatory molecules but produce responses that intermediate intensity o the maximal effect that a partial agonist can produce is less than that of a full agonist.
Image of page 20
antagonists: o block the actions of endogenous regulators o produce effects by preventing receptor activation by endogenous regulatory molecules and drugs o no effect by themselves on receptors but cause pharmacologic effects by preventing the activation of receptors by agonists. o affinity for a receptor but with no intrinsic activity. Therefore affinity and intrinsic activity are independent of each other (Modified Occupancy Theory). Intrinsic activity is the ability of a drug to activate the receptor following binding. Agonist/antagonist: o one drug that is agonist to some receptors and an antagonist to others. 21. Define the ED 50 and the LD 50 Effective dose in 50% of the population LD50 is lethal dose in 50% of the population. 22. Discuss the concept of a drug’s therapeutic index and its application and benefits to clinical practice, such as the relationships between the doses of a drug and whether its effects are sub-therapeutic (inadequate), therapeutic (desired response), or toxic (adverse effects related to excessive dosage). Measure of a drug’s safety. Measure of the ratio of LD50 (lethal dose in 50% of population) to ED50. LD50/ED50 A high therapeutic index (TI) is safe. A narrow range is not safe. A TI of 100 is safer than that of 4. 23. Discuss the consequences of drug-drug interactions, the basic mechanisms of drug-drug interactions, and the critical steps in minimizing adverse drug-drug interactions. May occur whenever a patient takes more than one drug Some interactions are intended/desired or unintended/undesired Sometimes when combined it can be life threatening, like bleeding When to take the medication, with food or empty stomach 1hr before or 2 hours after the meal for an empty stomach What the medications and what the indications are Medications can interact together and so we need to know what were taken in case of adverse medication interaction. It can increase effect, decrease it or unknown effect.
Image of page 21
Image of page 22

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture