Pharmacy Notes | Pharmacology | Anatomy Physiology | Exam Revison

Drug Discovery Drug discovery is the process of identifying and developing new medications to treat diseases and improve human health.  It involves a series of scientific and technological steps to identify potential drug candidates, evaluate their safety and efficacy , and bring them to market for clinical use.  The process typically involves several stages and interdisciplinary collaboration among researchers, chemists, biologists, pharmacologists, and clinicians. The drug discovery process can be summarized into the following steps: 1. Target Identification The first step is to identify a specific biological target, such as a protein or enzyme, that is involved in a disease process. This target is often selected based on its known association with the disease or its potential role in disease progression. 2. Lead Discovery In this stage, scientists search for molecules or compounds that have the potential to interact with the identified target. This is typically done through...

Drug Interactions Jane's Unexpected Reaction Meet Jane, a 65-year-old woman with high blood pressure and arthritis. She takes medication A, a calcium channel blocker, to manage her blood pressure, and medication B, a nonsteroidal anti-inflammatory drug (NSAID), for her arthritis pain. One day, Jane develops a severe headache and decides to take an over-the-counter medication, medication C, for quick relief. Medication C contains a common ingredient called acetaminophen (paracetamol), which is often used to reduce pain and fever. However, shortly after taking medication C, Jane experiences dizziness, lightheadedness, and a sudden drop in blood pressure. Concerned, she contacts her doctor who suspects a drug interaction . Drug Interaction Drug interaction refers to the phenomenon where the effects of one drug are altered when it is taken alongside another drug, or in the presence of certain foods, beverages, or other substances. Drug interactions can affect the  Pharmacokinetics Ph...

Adverse Drug Reactions (ADRs)  ADRs refer to unintended and harmful effects that occur as a result of medication use.  These reactions can range from mild and tolerable side effects to severe and life-threatening conditions.  ADRs can occur with any medication, including prescription drugs, over-the-counter drugs, and herbal or dietary supplements. ADRs can occur due to various reasons, including pharmacological effects, individual susceptibility , drug interaction, medication errors, etc. To ensure patient safety and minimize the occurrence of ADRs, healthcare professionals follow various strategies. These include: Thoroughly assessing a patient's medical history, including allergies, previous adverse reactions, and current medications, to identify potential risks. Selecting the most appropriate medication based on the individual patient's characteristics and considering factors such as age, organ function, and pregnancy status. Providing clear instructions on medicatio...

Pharmacodynamics II Signal Transduction Mechanisms 1. G-Protein Coupled Receptors (GPCRs) When a ligand, such as a hormone or a neurotransmitter, binds to a GPCR on the cell surface, it triggers a series of events inside the cell that leads to a specific response. Upon ligand binding, the GPCR undergoes conformational changes that result in the activation of a G protein located on the intracellular face of the plasma membrane. The activated G protein consists of three subunits (α, β, and γ), which dissociate upon activation and interact with downstream effector molecules to initiate intracellular signaling cascades. The α subunit is responsible for the interaction with the effector enzyme or ion channel, while the βγ subunit complex serves as a signal transducer. The type of G protein activated by a GPCR and the downstream signaling pathway initiated by the G protein depends on the specific type of GPCR and the ligand that binds to it. For example, the activation of Gαs by a GPCR l...