Table 1.

Comparison of pharmacology and metabolism of phenylephrine and pseudoephedrine [10, 11, 13, 15, 16]

	Phenylephrine	Pseudoephedrine
Adrenoceptor activity	Mainly α1	β and α1 indirect
CNS activity	None	weak stimulant
Presystemic metabolism	Gut and liver	None
Excretion in urine	3% unchanged	90% unchanged
Cardiovascular effects	Hypertension bradycardia	Hypertension bradycardia
Maximum dosage	10–12.2 mg every 4 h	60 mg every 4–6 h
Tmax (h) plasma	1.0–1.3	1.9
t1/2	2.0–3.0	5.4