Foreign regulatory status: Saw palmetto is approved as a drug with prescription status in Austria, Italy, and Poland (Vallancien and Pariente, 2001). It is approved as a drug with over-the-counter drug (OTC) status for use in various urinary problems associated with BPH in Switzerland, Sweden, and Denmark. In Spain, standardized lipid/sterol extracts are approved as a drug with prescription status, and nonstandardized extracts are approved as dietary supplements. In France, saw palmetto has OTC status but is primarily prescribed by physicians. In Germany, the Commission E has evaluated saw palmetto as safe and effective for urination problems in mild to moderate BPH; extracts of saw palmetto fruit have OTC status but are primarily prescribed by physicians (Blumenthal, 1998). In Canada, saw palmetto is authorized for sale as a traditional herbal medicine with the indication of increasing the flow of urine.
Very little is known about the digestion, absorption, distribution, metabolism, and excretion of some components of saw palmetto fruit (i.e., phenolic components, phytosterols, flavonoids, and polyprenoids). Other components have been well characterized (i.e., sugars, fatty acids, and other hydrocarbons).
Distribution: In a study of rats given a radioactive n-hexane LESP, tissue concentrations of radioactive labeled isolates of lauric acid, oleic acid, and β-sitosterol were highest in abdominal fat tissue, prostate, and skin. Lower concentrations were distributed to the liver and urinary bladder (Chevalier et al., 1997). No other studies reporting on the distribution of components of saw palmetto fruit were identified. Saw palmetto components were not clearly identified in any reports found in the literature.
Rectal administration: Extract of saw palmetto fruit was administered rectally (De Bernardi di Valserra and Tripodi, 1994) to show that the bioavailability and pharmacokinetic profile was quite similar to oral administration. Tmax occurred about 1 hour after administration and a component was still detectable in plasma after 8 hours.
Topical use: A lotion containing cystine and saw palmetto extract is of possible use in alopecia (Morganti et al., 1998).