Summary
Drug interactions occur when a drug's mechanism of action is affected by the concomitant administration of substances such as foods, beverages, or other drugs. The cause is often inhibition of, or less effective action, of the specific receptors available to the drug. This influences drug molecules to bind to secondary targets, which may result in an array of unwanted side-effects. The term selectivity describes a drug’s ability to target a single receptor, rendering a predictable physiological response. For example, the binding of acetylcholine to muscarinic tracheal smooth-muscle receptors (M3) results in smooth muscle contractions. When freely binding receptors interact with agonist- chemicals that activate receptors - and antagonists- that inhibit/ block activation - the opportunity for selective drugs to bind with the intended receptor cells decreases as most receptors are already accounted for. Therefore, the drugs are more likely to bind to other receptors relative to the intended receptor, causing different effects. For example, consuming both Zolpidem (i.e., Ambien) and alcohol together, both which affect the GABAA receptors, results in the overstimulation of this receptor, which can lead to loss of consciousness. The risk of a drug-drug interaction (DDI) increases with the number of drugs used. Over a third (36%) of the elderly in the U.S. regularly use five or more medications or supplements, and 15% are at risk of a significant drug-drug interaction. Drug interactions can be additive (the result is what you expect when you add together the effect of each drug taken independently), synergistic (combining the drugs leads to a larger effect than expected), or antagonistic (combining the drugs leads to a smaller effect than expected). On some occasions, it is difficult to distinguish between synergistic or additive interactions, since the individual effects of each drug may vary from patient to patient. A synergistic interaction may be beneficial for patients, but may also increase the risk of overdose.
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related courses (6)
BIO-494: Scientific project design in drug discovery
The goal of this course is to instruct the student how fundamental scientific knowledge can be applied for drug discovery and development. We will demonstrate these principles with examples, including
BIO-478: Pharmacology and pharmacokinetics
This course introduces the student to the fudamentals of pharmacology, pharmacokinetics and drug-receptor interactions. It discusses also pharmacogenetics and chronopharmacology, to exemplify the chal
CH-602: Basic principles of drug action at the cardiovascular system
The aim of this course is two-fold:
  • to describe the molecular properties of some important drug targets
  • to illustrate some applications of drugs active at the nervous and cardiovascular systems.
Show more
Related lectures (32)
Facing Fearful Odds
Explores the concept of facing fearful odds and dying well.
Selective Drug Targeting Mechanisms
Explores selective drug targeting mechanisms, resistance development, tuberculosis incidence, BCR-ABL mutations, tyrosine kinase inhibitors, drug toxicity, interactions, and toxicology studies.
Interrogating Drugs' Mode of Action
Delves into enzyme inhibition, reversible and irreversible binding, and covalent drugs, exploring drug modes of action and their impact on drug efficacy.
Show more
Related publications (98)
Related concepts (34)
Adverse effect
An adverse effect is an undesired harmful effect resulting from a medication or other intervention, such as surgery. An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect. The term complication is similar to adverse effect, but the latter is typically used in pharmacological contexts, or when the negative effect is expected or common. If the negative effect results from an unsuitable or incorrect dosage or procedure, this is called a medical error and not an adverse effect.
Omeprazole
Omeprazole, sold under the brand names Prilosec and Losec, among others, is a medication used in the treatment of gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger–Ellison syndrome. It is also used to prevent upper gastrointestinal bleeding in people who are at high risk. Omeprazole is a proton-pump inhibitor (PPI) and its effectiveness is similar to that of other PPIs. It can be taken by mouth or by injection into a vein.
Cytochrome P450
Cytochromes P450 (P450s or CYPs) are a superfamily of enzymes containing heme as a cofactor that mostly, but not exclusively, function as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are important for the clearance of various compounds, as well as for hormone synthesis and breakdown. In 1963, Estabrook, Cooper, and Rosenthal described the role of CYP as a catalyst in steroid hormone synthesis and drug metabolism.
Show more