Tachyphylaxis
Definition:
When responsiveness diminishes rapidly after the administration of a drug.
Relevance:
Tachyphylaxis results in loss of efficacy of a drug and needs to be taken into account when dosing and prescribing. Strategies that take drug tachyphylaxis into account include, requiring drug-free intervals and giving the drug in combination with other drugs. However, more often, drugs that display tachyphylaxis have limited therapeutic potential for long-term use.
Examples:
Nitroglycerine (and other nitrovasodilators)
Hydralazine
Ranitidine
Linked terms: Tolerance, desensitization
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