<< do you know if thyroid antibodies are directed against the gland or against the hormones ? >> Thyroid antibodies gradually destroy the gland. Symptoms of hypothyroidism (underactive thyroid) occur as it becomes increasingly difficult for the gland to function normally. << Could thyroid antibodies make the intake of synthetic hormones not active? >> No, thyroid medication replaces what the gland is no longer able to produce in adequate quantities for the body to function normally. Lynda Bryson [log in to unmask] __________________________________________________ Do you Yahoo!? The New Yahoo! Search - Faster. Easier. Bingo http://search.yahoo.com