A corona virus  is a kind of common virus that causes an infection in nose, sinuses, or upper throat. In early 2020, after a December 2019 outbreak in China, the World Health Organization identified SARS-CoV-2 as a new type of corona virus. The outbreak quickly spread around the world. COVID-19 is a disease caused by SARS-CoV-2 that can trigger a respiratory tract infection. It can affect upper respiratory tract (sinuses, nose, and throat) or lower respiratory tract (windpipe and lungs). It spreads the same way as other co.ronaviruses do, mainly through person-to-person contact. Infections range from mild to deadly. The virus can lead to pneumonia, respiratory failure, septic shock and death. Many COVID-19 complications may be caused by a condition known as cytokine release syndrome or a cytokine storm

A receptor is a protein molecule that receives chemical signals from outside a cell. The structures of receptors are very diverse and can broadly be classified into L (Ionic receptors), G protein couple receptors (metabotropic), Kinase-linked and related receptors, Nuclear receptors. Drugs interact with receptors by bonding at specific binding sites. Most receptors are made up of proteins, and the drugs can therefore interact with the amino acids to change the conformation of the receptor proteins. Drugs interact with receptors by bonding at specific binding sites. Most receptors are made up of proteins, and the drugs can therefore interact with the amino acids to change the conformation of the receptor proteins. Drug mechanism of action is determined by Microscopy-based methods, direct biochemical method, Computation inference methods. When talking about the shape of molecules, biochemists are mainly concerned with the three-dimensional conformation of drug molecules. There are many isomers of a particular drug, and each one will have its own effects. Differences in isomer affect not only what the drug activates, but also changes the potency of each drug.

The metabolism of drugs and other xenobiotics into more hydrophilic metabolites is essential for the elimination of these compounds from the body and termination of their biological activity. The liver is the principal site of drug metabolism. Although metabolism typically inactivates drugs, some drug metabolites are pharmacologically active—sometimes even more so than the parent compound. Drug Metabolism is concerned with Permeability barriers and detoxification, Phases of detoxification, Endogenous toxins and the factors that affect drug metabolism. Excretion is a process whereby drugs are transferred from the internal to the external environment. Despite the reduction in activity that occurs as a drug leaves its site of action, it may remain in the body for a considerable period, especially if it is strongly bound to tissue components. Excretion, along with metabolism and tissue redistribution, is important in determining both the duration of drug action and the rate of drug elimination. Principal organs involved Kidneys, Lungs, Biliary system, Intestines, Saliva, and Milk.

The idea that the effect of a drug in the human body is mediated by specific interactions of the drug molecule with biological macromolecules, (proteins or nucleic acids in most cases) led scientists to the conclusion that individual chemicals are required for the biological activity of the drug. The first step in the drug discovery process is to identify a suitable target. This is a molecule or a protein receptor that is specifically associated with a disease condition or pathology. For this purpose, it is important to understand how the disease occurs at the molecular, cellular, and genetic levels. The drug development phase involves rigorous testing and optimization of the selected compounds to identify the lead structure or candidate drug’ which might be the most effective. Testing required by the health authorities is done in cells (in vitro) and in animals (in vivo) to study metabolism safety, toxicity, dosage, and efficacy.

Pharmacokinetics is the quantitative study of drug movement in, through and out of the body. Intensity of effect is related to concentration of the drug at the site of action, which depends on its pharmacokinetic properties and these properties of particular drug is important to determine the route of administration, dose, onset of action, peak action time, duration of action and frequency of dosing. Pharmacodynamics is the branch of pharmacology concerned with the action of drugs on the body or on microorganisms within or on the body.

Pharmacoepidemiology is the study of drug efficacy, toxicity and patterns of use in large populations. Thus, pharmacoepidemiology can be called a bridge science spanning both pharmacology and epidemiology. Pharmacoepidemiology sometimes also involves the conduct and evaluation of programmatic efforts to improve medication use on a population basis.  Pharmacovigilance is a type of continual monitoring for unwanted effects and other safety-related aspects of drugs that are already on the market. Pharmacovigilance has been defined by the World Health Organisation as “The science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other possible drug-related problem”

Pharmacogenetics is the study of how the actions of and reactions to drugs vary with the patient's genes. Pharmacogenetics studies the genetic variation between people underlying differential response to drugs. Genes determine the make-up of all the body's proteins, and as medicines travel through the body they interact with many of these proteins. This relatively new field allows us to combine pharmacology and genomics to develop effective and safe medication dosages which are specific to an individual’s DNA makeup.  

Pharmaceutical engineering is a branch ofpharmaceutical science and technology that involves development and manufacturing of products, processes, and components in the pharmaceuticals industry. A pharmaceutical engineer is a specialized chemical engineer who focuses on creating new pharmaceutical drugs and improving upon existing products and manufacturing processes. Pharmaceutical engineering is subject to various regulations in different countries, and pharmaceutical engineers must ensure they maintain personal and environmental safety at all times.

Pharmaceutical formulation is a process in which different chemical substances i.e., active chemical substances will combined together to produce a medical compound i.e., medical drug. The pharmaceutical formulations process involves the entire process of a how a drug is developed and how it is finally accepted by the patient. The drug form varies by the route of administration. Like capsules , tablets and pills etc. Parenteral formulations also called injectable formulations and are used with intravenous, subcutaneous, intramuscular, and intra-articular administration. In the pharmaceutical drug formulations, the different physical, chemical, and mechanical properties of a drug are considered so as to know what other ingredients should be used in the preparation.

Pharmaceutical Microbiology is an applied branch of Microbiology. It involves the study of microorganisms associated with the manufacture of pharmaceuticals like minimizing the number of microorganisms in a process environment, excluding microorganisms and microbial by-products like exotoxin and endotoxin from water and other starting materials, and ensuring the finished pharmaceutical product is sterile. The most important contribution of microbiology to the pharmaceutical industry is the development of antibiotics. Apart from drugs and bio products development, microbiology contributes towards quality control of a pharmaceutical laboratory. Prevention of microbial contamination of drugs, injectables, eye drops, nasal solutions and inhalation products is undertaken following pharmacopeial guidelines. 

Pharmacognosy is the study of medicines or crude drugs produced from natural sources such as plants, microbes, and animals. It includes analysis of their biological, chemical, biochemical, and physical properties. It includes the study of various disciples such as ethnobotony, ethnopharmacology, Phytotherapy, Phytochemistry, Zoopharmacognosy, Marine pharmacognosy etc. The part of pharmacognosy focusing on the use of crude extracts or semi-pure mixtures originating from nature, namely phytotherapy, is probably the best known and also the most debated area in pharmacognosy.

Medicinal chemistry is the chemistry discipline concerned with the design, development and synthesis of pharmaceutical drugs. The discipline combines expertise from chemistry and pharmacology to identify, develop and synthesize chemical agents that have a therapeutic use and to evaluate the properties of existing drugs.

Biopharmaceutics is the study of the physical and chemical properties of a drug, and its dosage form, as related to the onset, duration, and intensity of drug action, including coconstituents and mode of manufacture. Different from totally synthesized pharmaceuticals, they include vaccines, blood, blood components, allergenics, somatic cells, gene therapies, tissues, recombinant therapeutic protein, and living cells used in cell therapy. Biopharmaceuticals are majorly extracted from living systems (Whole blood and other blood components, Organs and tissue transplants, Stem cell therapy, Antibodies for passive immunization, Human breast milk, Fecal microbiota, Human reproductive cells) produced by recombinant DNA (Body’s own signelling proteins like Erythropoetin, Human insulin etc and other Monoclonal antibodies and fusion proteins) Major kinds of biopharmaceuticals include Blood factors, Thrombolytic agents, Hormones, Haematopoietic growth factors, Interferons, Interleukin-based products, Vaccines, Monoclonal antibodies etc.

Pharmacotherapy is the Study of the use and effects produced by drugs on patients as well as the treatment of illnesses by administering drugs. Pharmacists are experts in pharmacotherapy and are responsible for ensuring the safe, appropriate, and economical use of pharmaceutical drugs. The skills required to function as a pharmacist require knowledge, training and experience in biomedical, pharmaceutical and clinical sciences.

Clinical pharmacy is the branch of pharmacy in which pharmacists provide patient care that optimizes the use of medication and promotes health, wellness, and disease prevention. Clinical pharmacists often work in collaboration with physicians, nurse practitioners, and other healthcare professionals. Transitional care refers to the coordination and continuity of health care during a movement from one healthcare setting to either another or to home, called care transition, between health care practitioners and settings as their condition and care needs change during the course of a chronic or acute illness. By integrating pharmacy and medical data, clients gain the visibility needed to make informed decisions with regard to the pharmacy benefits offered to their members.

Hospital Pharmacy is a department or service in a hospital, responsible for the supply of medications to hospital wards as well as ambulatory patients, The department is headed by professionally competent, legally qualified pharmacist who directly supervises and ensures the correct dispensing, compounding, and distribution of medication to in and out-patients. The major goals include providing the benefits of a qualified hospital pharmacist to patients and health care institutions, to the allied health professions, and to the profession of pharmacy, To assist in providing an adequate supply of such qualified hospital pharmacists, To assure a high quality of professional practice through the establishment and maintenance of standards of professional ethics, education, and attainments and through the promotion of economic welfare, To promote research in hospital pharmacy practices and in the pharmaceutical sciences in general, To disseminate pharmaceutical knowledge by providing for interchange of information among hospital pharmacists and with members of allied specialties and professions.

Pharmaceutical Management is a division of management that deals with chemical and health sciences and ensures the effective and safe use of pharmaceutical drugs.  Pharmaceutical Management integrates business strategy with science and technology and the unique perspective of the industry. 

Validation is establishing documented evidence which provides a high degree of assurance that a specific process or equipment will consistently produce a product or result meeting its pre-determined specification and quality attributes. Validation is a key process for effective Quality Assurance. A GMP is a system for ensuring that products are consistently produced and controlled according to quality standards. It is designed to minimize the risks involved in any pharmaceutical production that cannot be eliminated through testing the final product. GMP covers all aspects of production from the starting materials, premises and equipment to the training and personal hygiene of staff.

Pharmaceutical Chemistry is the science of design and chemical synthesis of a drug or a molecule by the application of analytical techniques. It is majorly involved in drug design and its synthesis. Pharmaceutical Chemistry is applied in laboratories either to discover a new API (Active Pharmaceutical Ingredient) or to enhance the bioavailability of an existing drug or a molecule by either rearranging the structure of the molecule or by modifying its synthesis. These studies are generally performed for low potent drugs to increase their pharmacological activity. Pharmaceutical Chemistry includes organic, inorganic chemistry and analytical chemistry related to pharmaceuticals and other biomolecules.

Pharmaceutical analysis in drug development mainly focuses on methods to identify and quantify potential new drug candidates, determine purity, identify by – products and degradation products in compatibility and stability studies, and to determine the drug substance’s fate in the organism.

Biological research can be compared with the role of data analysis in the age of information and the Internet. In earlier days, the primary challenge was getting to the information. Advances in reading DNA sequences have lowered that barrier substantially. Going forward, the challenge is how to understand and interpret the information that has been collected. Because the data sets are large, whether you're talking about information about website visits or the human genome, computer-based methods are the default approach. In the end, bioinformatics work with human genomes seeks to discover practical insights about human health and biology with all its complexity.