Monday, August 16, 2021

Drug Synergism

 When two drugs are administered simultaneously, not necessarily by the same route,the drugs may act in the same or opposite directions. This phenomenon is known as drug  synergism.

 Literally, synergism means working together.

Synergism can be positive or negative.

 In positive synergism, the effect of two drugs combined together is greater than the sum of the effect of the two drugs used singly. 

Positive synergism is also known as supra-additive effect or potentiation. 

In negative synergism, the effect of the two drugs combined together is less than the sum of the effect of the drugs used singly. 

Negative synergism is better known as antagonism. 

In some synergistic combination, the effect of the two drugs combined together is simply the sum of the effect of the two drugs used singly. This is known as additive synergism.

 Additive synergism is useful in conditions where the dose of the two drugs in combination can be reduced to minimize the side effects associated with the individual drugs.

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