Additive drug effect means that the combination is?

Additive drug effect means that the combination is?

• A. SUM of individual effects
• B. Exceeds the sum of individual effects
• C. Less than the sum of individual effects
• D. Has no interaction

Answer: (A)

Additive effect means the two drugs’ effects simply add together. When each drug has a certain amount of effect on its own, the combined effect equals the arithmetic sum of those individual effects (up to the maximum possible response). For example, if one drug provides 20% relief and another provides 15% relief, the combination yields about 35% relief. This is different from synergy, where the combo exceeds the sum, or antagonism, where the combo is less than the sum.

Additive effect means the two drugs’ effects simply add together. When each drug has a certain amount of effect on its own, the combined effect equals the arithmetic sum of those individual effects (up to the maximum possible response). For example, if one drug provides 20% relief and another provides 15% relief, the combination yields about 35% relief. This is different from synergy, where the combo exceeds the sum, or antagonism, where the combo is less than the sum.