In ecology, commensalism is a class of relationship between two organisms where one organism benefits without affecting the other. It compares with mutualism, in which both organisms benefit, amensalism, where one is harmed while the other is unaffected, and parasitism, where one benefits while the other is harmed.n ecology, commensalism is a class of relationship between two organisms where one organism benefits without affecting the other. It compares with mutualism, in which both organisms benefit, amensalism, where one is harmed while the other is unaffected, and parasitism, where one benefits while the other is harmed.
Drug interactions also may occur when two drugs that have similar (additive) effects or opposite (canceling) effects on the body are administered together. For example, there may be major sedation when two drugs that have sedation as side effects are given, for example, narcotics and antihistamines.
Cytochrome P450. Drug Interactions Table. Use of this Table: â¢ Definitions. Substrates: drugs that are metabolized as substrates by the. enzyme. Inhibitors: drugs that prevent the enzyme from metabolizing. the substrates. Activators: drugs that increase the enzymeâs ability to. metabolize the substrates. â¢ The table contains lists of drugs in columns under the. designation of specific cytochrome P450 isoforms. A drug. appears in a column if there is published evidence that it is. metabolized, at least in part, via that isoform.