Posted: October 5th, 2023

Pathophysiology and Pharmacology

Pathophysiology and Pharmacology

Pathophysiology is the study of how diseases affect the normal functioning of the body. It explains the mechanisms and processes that underlie the signs and symptoms of various disorders. Pharmacology is the science of drugs and their interactions with living systems. It covers the sources, properties, effects, and uses of drugs in medicine. Pathophysiology and pharmacology are closely related fields that help us understand and treat human diseases.

In this blog post, we will provide an overview of some core concepts and key pathophysiological processes that are relevant to nursing practice. We will also discuss some common pharmacological agents that are used to manage these conditions. We will focus on inflammation, infection, and cancer, as well as some examples of disorders affecting different body systems.

Inflammation

Inflammation is a protective response of the body to injury, infection, or irritation. It involves a complex series of events that aim to eliminate the cause of damage, remove dead or damaged cells, and initiate tissue repair. The main features of inflammation are redness, heat, swelling, pain, and loss of function.

The inflammatory response is mediated by various cells, molecules, and pathways that coordinate the recruitment of immune cells, the release of inflammatory mediators, the dilation of blood vessels, the increase of vascular permeability, and the activation of clotting factors. Some of the key players in inflammation are mast cells, macrophages, neutrophils, lymphocytes, cytokines, prostaglandins, histamine, bradykinin, complement system, and coagulation cascade.

Pharmacological agents that are used to modulate inflammation include anti-inflammatory drugs (such as aspirin, ibuprofen, corticosteroids), antihistamines (such as diphenhydramine), antipyretics (such as paracetamol), and immunosuppressants (such as cyclosporine).

Infection

Infection is the invasion and multiplication of microorganisms (such as bacteria, viruses, fungi, parasites) in the body that cause harm or disease. Infection can be localised or systemic, acute or chronic, primary or secondary. The outcome of infection depends on the balance between the virulence of the microorganism and the host’s immune response.

The immune system is composed of innate and adaptive components that work together to recognise and eliminate foreign invaders. The innate immune system consists of physical barriers (such as skin and mucous membranes), chemical barriers (such as lysozyme and acid), cellular defenses (such as phagocytes and natural killer cells), and inflammatory response. The adaptive immune system consists of humoral immunity (mediated by antibodies produced by B lymphocytes) and cell-mediated immunity (mediated by T lymphocytes).

Pharmacological agents that are used to combat infection include antimicrobial drugs (such as antibiotics, antivirals, antifungals), vaccines (which stimulate active immunity), immunoglobulins (which provide passive immunity), and immunomodulators (such as interferons).

Cancer

Cancer is a group of diseases characterised by uncontrolled growth and spread of abnormal cells that can invade and destroy normal tissues. Cancer can arise from any cell type in any organ or tissue in the body. The main causes of cancer are genetic mutations (either inherited or acquired) that affect genes involved in cell cycle regulation, DNA repair, apoptosis, differentiation, angiogenesis, invasion, and metastasis.

The process of cancer development involves several stages: initiation (when a normal cell acquires a mutation that confers a growth advantage), promotion (when the mutated cell proliferates under the influence of external factors), progression (when the cancer cells acquire more mutations that enhance their survival and aggressiveness), and metastasis (when the cancer cells spread to other parts of the body through blood or lymph vessels).

Pharmacological agents that are used to treat cancer include cytotoxic drugs (which kill rapidly dividing cells), targeted drugs (which interfere with specific molecules or pathways involved in cancer growth or survival), hormonal drugs (which block or mimic hormones that stimulate certain cancers), immunotherapy drugs (which enhance or suppress the immune system’s ability to fight cancer), and radiotherapy drugs (which enhance the effects of radiation therapy).