The U.S. Food and Drug Administration has warned several pharmacies about making unsubstantiated claims about the safety and effectiveness of compounded hormone products. The North American Menopause Society has stated that compounded bioidentical hormones have not been approved by the FDA; there is no guarantee of purity, potency, efficacy or safety, and they may contain unknown contaminants. The Australian Menopause Society has similarly stated that there is no evidence that bioidentical hormones administered using lozenges are any safer than their approved counterparts. The International Menopause Society has stated "There are no medical or scientific reasons to recommend unregistered 'bioidentical hormones'. The measurement of hormone levels in the saliva is not clinically useful. These ‘customized’ hormonal preparations have not been tested in studies and their purity and risks are unknown."