Phenylephrine's efficacy as a decongestant when taken orally is dubious. Still, it doesn't mean it's a useless drug. IV phenylephrine is a standard drug used du

Phenylephrine's efficacy as a decongestant when taken orally is dubious. Still, it doesn't mean it's a useless drug. IV phenylephrine is a standard drug used during anesthesia to counteract the hypotensive effects of opioids and sedatives.