Phyllostegia bracteata is a scandent herb with a somewhat woody base and curved hairs on the stems. Ovate leaves are membranous, 2 to 6 inches (in) (5 to 15 centimeters (cm)) long, 1 to 2.6 in (2.6 to 6.5 cm) wide, with crenate margins. Both surfaces of the leaves are pubescent with the lower surface densely dotted with glands. Flowers have a slightly curved white corolla and are born on racemose inflorescences 4 to 12 in (10 to 30 cm) long. Nutlets are up to 2.5 mm (0.1 in) long.