Pharmacotherapy

From natural compounds to pharmaceutical drugs The use of medicinal substances can be traced back to 4000 BC in the Sumer civilization. Healers at the time (called apothecaries), for example, understood the application of opium for pain relief. The history of natural remedies can also be found in other cultures, including traditional Chinese medicine in China and Ayurvedic medicine in India, which are still in use nowadays. Dioscorides, a 1st -century Greek surgeon, described more than six hundred animals, plants, and their derivatives in his medical botany, which remained the most influential pharmacopeia for fourteen hundred years. Besides substances derived from living organisms, metals, including copper, mercury, and antimony, were also used as medical therapies. However, due to the concern over acute and chronic antimony poisoning, the role of tartar emetic as an antischistosomal agent was gradually replaced after the advent of praziquantel. The Penicillium mold on the petri dish was believed to secrete a substance (later named "penicillin") that inhibited bacterial growth. The screening program for antimicrobial compounds also led to the discovery of drugs with other pharmacological properties, such as immunosuppressants like Cyclosporin A. Receptors were believed to be the specific binding sites for drugs. It was later found that the receptors can either be stimulated or inhibited by chemotherapeutic agents to attain the desired physiological response. Once the ligand interacting with the target macromolecule is identified, drug candidates can be designed and optimized based on the structure-activity relationship. Nowadays, artificial intelligence is employed in drug design to predict drug-protein interactions, drug activity, the 3D configuration of proteins, etc. == Evidence-based medicine ==

Evidence-based medicine is defined as deploying the best current scientific evidence that is available to give the best treatment and make the best decision effectively and efficiently. Clinical guidelines are developed based on scientific evidence; for example, the ACC/AHA guidelines (for cardiovascular diseases), the GOLD guidelines (for chronic obstructive pulmonary disease), the GINA guidelines (for asthma), etc. They convert and classify the evidence using a systematic method, aiming to provide care with quality. The guidelines cannot substitute clinical judgment, as they cannot meet all the circumstances. The first-line therapy will be either an Angiotensin Converting Enzyme Inhibitor (ACEi) or an Angiotensin receptor blocker (ARB) (if the patient cannot tolerate ACEi). or a Thiazide-like diuretic to the previous therapy, i.e., ACEi or ARBs with a CCB or a thiazide-like diuretic. == Personalized medicine ==

Every patient has their own body condition, for example, kidney function, liver function, genetic variations, medical history, etc. These are all the factors that should be considered by healthcare professionals before giving any pharmacological therapy. Most importantly, the advancing technology in genetics guides us to have more insight into the linkage between health and genes. In pharmacological therapy, two areas of study are evolving: pharmacogenetics and pharmacogenomics. Age will affect the pharmacokinetics and pharmacodynamics of drugs, and hence the efficacy of the therapy. The effect of age causes deterioration of organ function, like liver function and kidney function. Pharmacokinetics is the study of drugs' effects on absorption, distribution, metabolism, and elimination. Pharmacodynamics is the study of drugs' effects on our body and their mechanisms. === Pharmacogenetics and pharmacogenomics === Pharmacogenetics is defined as the study of inherited genes causing different drug metabolisms that vary from each other, such as the rate of metabolism and metabolites. Pharmacogenomics is defined as the study of associating the drug response with one's gene. Both terms are similar in nature, so they are used interchangeably. Multiple alleles can contribute together to a change in response to a drug by expressing a different form of an enzyme that responds differently than the normal ones. The genetic make-up can affect the pharmacokinetics. Example: Azathioprine Therapy Azathioprine is an immunomodulator for inflammatory bowel disease, for instance. Its metabolite relies on two different enzymes (TPMT and NUDT15) to eliminate its effect on our body during its metabolism. If the patient has the phenotype of the enzymes that metabolize it poorly, i.e., the poor metabolizer, more toxic metabolites are accumulated in the body. Thus, the patient has a greater risk of the related side-effect. The side effect causes the adjustment of dosage It targets the immunoglobulin E (IgE) in human body, which plays an important role in allergic reactions. The efficacy of omalizumab may vary among patients. To identify responders to omalizumab, the level of several biomarkers can be measured, including serum eosinophils, fractional exhaled nitric oxide, and serum IgE. For instance, patients with higher baseline eosinophil counts are likely to respond better to omalizumab therapy. == Medication compliance ==

Medication compliance is defined as the degree to which the patient follows the therapy that is recommended by healthcare professionals. while the indirect method includes pill counting This is to increase medication compliance. This is to prevent treatment failure, relapse, and transmission in the community. Apart from the traditional direct observed therapy (DOT), there is another method proposed to try increasing medication compliance. Video-observed therapy (VOT) is one of the methods. It has some advantages and disadvantages. It reduces the cost of healthcare and the travel costs for the patient. The downside of the intervention is the need for quality control training as it would be hard to confirm the patient's adherence. ==Role of Pharmacists==

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. Pharmacology is the science that aims to continually improve pharmacotherapy. The pharmaceutical industry and academia use basic science, applied science, and translational science to create new pharmaceutical drugs. As pharmacotherapy specialists and pharmacists have responsibility for direct patient care, often functioning as a member of a multidisciplinary team, and acting as the primary source of drug-related information for other healthcare professionals. A pharmacotherapy specialist is an individual who is specialized in administering and prescribing medication, and requires extensive academic knowledge in pharmacotherapy. In the US, a pharmacist can gain Board Certification in the area of pharmacotherapy upon fulfilling eligibility requirements and passing a certification examination. While pharmacists provide valuable information about medications for patients and healthcare professionals, they are not typically considered covered pharmacotherapy providers by insurance companies. == See also ==