When the fragrance of a perfume is inhaled, it doesn't just pass through the olfactory circuit.

Your skin, and thus your entire body, also absorb micro-droplets. Even though the quantity is small, it should not be overlooked.

Grapefruit juice is an inhibitor of enzymes found in the liver and small intestine (CYP3A4). It hinders the metabolism of certain chemical compounds. Nearly 50 medications (including immunosuppressants) are documented to have interactions with grapefruit juice.

In other words, grapefruit can alter the effectiveness of a medicinal treatment. This is why you won't find grapefruit in La Bastide d’Isalinore products.