<unk> s have their primary mechanism of action outside of the central nervous system (CNS), usually because they are excluded from the CNS by the blood-brain barrier. By being excluded from the CNS,<unk> s may act on the rest of the body without producing side-effects related to their effects on the brain or spinal cord. For example, most opiates cause sedation when given at a sufficiently high dose, but<unk><unk>  opiates can act on the rest of the body without entering the brain and are less likely to cause sedation.
Peripherally selective drug
Mercurial diuretic
Virtually safe dose
Antipruritic
Small modular immunopharmaceutical
Salt substitute
Anticoagulant
New chemical entity