Pharmacological evaluation revealed that use of uva ursi led to an increase in urine flow.
– Phytother Res 1999 May;13(3):222-5 — Effect of extracts of Orthosiphon stamineus Benth, Hieracium pilosella L., Sambucus nigra L. and Arctostaphylos uva-ursi (L.) Spreng. in rats. — Beaux D, Fleurentin J, Mortier F.
Possible skin reaction to hydroquinone in uva ursi.
– S Afr Med J 1975 Aug 9;49(34):1391-5 — Cutaneous reactions to topical application of hydroquinone. Results of a 6-year investigation. — Bentley-Phillips B, Bayles MA.
May cause temporary or permanent discoloration of the skin.
Neurologic effects of hydroquinone include headache, tinnitus, dizziness, delirium, muscle twitching, tremor, and convulsions. Nausea, vomiting, and the production of green to brown-green urine may also occur. Hydroquinone
may be irritating and corrosive to the skin, eyes, and mucous membranes. Jaundice (yellow tint to skin) may be noticed. Ingestion of hydroquinone may result in sudden onset of seizures or loss of consciousness. Liver toxin, carcinogen, and irritant.
– Enviromental Protection Agency — www.epa.gov