In adults, the condition refers to any penis smaller than 2.8 inches in length. (2) In infants, a Micropenis is classed as any penis that is less than 0.75 inches in length. This is considered significantly smaller than a ânormalâ male newbornâs penis, which is between 1.1 and 1.6 inches in length when stretched gently.
drug-drug interaction, a modification of the effect of a drug when administered with another drug. The effect may be an increase or a decrease in the action of either substance, or it may be an adverse effect that is not normally associated with either drug.he effect may be an increase or a decrease in the action of either substance, or it may be an adverse effect that is not normally associated with either drug.
Interactions between medications (drug interactions) fall generally into one of two main categories: 1  pharmacodynamic : Involving the actions of the two interacting drugs. 2  pharmacokinetic : Involving the absorption, distribution, metabolism, and excretion of one or both of the interacting drugs upon the other.