How long does phenylephrine stay in your system?

How long a drug stays in your system is a very difficult question to answer. It is dependant on many factors e.g.
1. How much and how often you have taken the drug.
2. Your metabolic rate – a slower metabolism will increase the time a drug remains in your system.
3. Your age and health – older age and poor health will generally increase the time the drug stays in your system.
4. Body mass – generally the bigger you are the longer a drug will remain in your system.

Phenylephrine has a half life of about 2 1/2 hours.