In toxicology,
synergism
refers to the effect caused when exposure to two or more chemicals at one time results in health effects that are greater than the sum of the effects of the individual chemicals.
When one drug increases the effect of another drug?
A
drug interaction
has occurred when the administration of one drug alters the clinical effects of another. The result may be an increase or decrease in either the beneficial or harmful effects of the second agent.
When the combined effects of two or more drugs is greater than the effect of each agent added together this effect is called?
Synergy
is commonly defined as the effect of two or more agents working in combination that is greater than the expected additive effect of said agents (Greco et al., 1996).
When is the combined effect of two drugs?
When two drugs are used together, their effects 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).
What term refers to when drugs increase each other’s effects when taken together?
Pharmacodynamic interactions
. The term “pharmacodynamic interactions” refers to interactions in which drugs influence each other’s effects directly.
What are 3 types of drug interactions?
Types of drug-drug interactions include
duplication, opposition (antagonism), and alteration of what the body does to one or both drugs
.
Which are the factors modifying drug action?
This chapter, therefore, deals with the following factors which modify drug action: (1)
route of administration, (2) rate and degree of absorption
, (3) rate of elimination, (4) effect of other drugs, (5) tolerance, (6) idiosyncrasy and allergy, (7) disease.
Which is the most common type of drug interaction?
pharmacokinetic
– defined as an alteration in the absorption, distribution, metabolism or excretion of one drug by another. This is the most common type of drug interaction. pharmacodynamic – where the drug affects the action or effect of the other drug.
Which medicines should not be taken together?
- Dangerous duo: Tylenol and multi-symptom cold medicines. …
- Dangerous duo: Any combo of ibuprofen, naproxen, and aspirin. …
- Dangerous duo: Antihistamines and motion-sickness medications. …
- Dangerous duo: Anti-diarrheal medicine and calcium supplements. …
- Dangerous duo: St.
What is a synergistic drug effect?
Synergism, Synergy.
An interaction between two or more drugs that causes the total effect of the drugs to be greater than the sum of the individual effects of each drug
. A synergistic effect can be beneficial or harmful.
What is an idiosyncratic effect?
Idiosyncratic drug reactions may be defined as
adverse effects that cannot be explained by the known mechanisms of action of the offending agent
, do not occur at any dose in most patients, and develop mostly unpredictably in susceptible individuals only.
What is an antagonistic effect?
Definition:
A biologic response to exposure to multiple substances that is less than would be expected if the known effects of the individual substances were added together
.
Which route of medication administration has the slowest onset of action?
The
intramuscular and subcutaneous routes
can be used to achieve slow or delayed onset of action.
What are the three possible types of interactions when two or more drugs are used?
- Interactions of drugs with other drugs (drug-drug interactions),
- Drugs with food (drug-food interactions)
- Drug with disease condition (drug-disease interactions).
What is a potentiating effect?
Potentiation – This effect results
when one substance that does not normally have a toxic effect is added to another chemical
, making the second chemical much more toxic; for example: 0 + 2 > 2, not just 2. Antagonism – Antagonism is the opposite of synergism.
How can you tell if two drugs are synergistic?
Two or more drugs that individually produce overtly similar effects will sometimes display greatly enhanced effects when given in combination.
When the combined effect is greater than that predicted by their individual potencies
, the combination is said to be synergistic.