muscles having opposite effects; the contraction of one neutralizes the contraction of the other.

Agents that competitively bind with the binding sites of agonists and thereby inhibit the agonist's actions.

Molecules that prevent activation of receptors in tissues. See ligand, agonist.

drugs that limit or prevent the action of a neurotransmitter, often by limiting the amount of chemical available.

Drugs that impede the activity of a neurotransmitter, often by decreasing the amount available (e.g., by speeding reuptake and decreasing availability of precursors).

drugs that block cellular response.

Remedies that will counteract the action of other remedies, or oppose their action.

Organisms that release toxins or otherwise change conditions so that activity or growth of the pest organism is reduced.