Butterbur, a herbal remedy, is as good as antihistamines but without the sedating side effects.
The standard antihistamine treatments for allergic rhinitis (hay fever) are effective, but often cause drowsiness, which is inconvenient or even dangerous if you are driving, or operating machinery.

Researchers in Switzerland now report a trial comparing a herbal remedy known as butterbur with cetirizine, an antihistamine, in allergic rhinitis.

The leaves and roots of butterbur - also known as bog rhubarb or butter dock - contain active ingredients called petasines which have an anti-inflammatory effect. A group of 125 people in this trial were assigned to either butterbur extract tablets or cetirizine. They found relief from rhinitis symptoms in both cases. But the antihistamine gave rise to the expected sedating side effects, while butterbur did not. Evidently it's worth considering butterbur as a positive alternative treatment for allergic rhinitis.

Source

British Medical Journal January 19 2002