The US FDA has assigned the pregnancy category B status to Benadryl, which means that it is considered safe to use, as there are no known side effects. However, your doctor will be the best person to judge whether or not you should take Benadryl while you are pregnant. He will also decide on the quantity of intake.
Human carcinogen -- Benzene: Benzene is a chemical deemed to be carcinogenic to humans. The carcinogenicity of the substance may be influenced by the nature (e.g. inhalation, ingestion, skin contact), duration and level of exposure. Benzene exposure is associated mainly with an increased risk of developing leukemia or lymphoma.
Benzene is a solid below 42Â°F (5.6Â°C). DESCRIPTION: Benzene is used to make chemicals used in the manufacture of industrial products such as dyes, detergents, explosives, pesticides, synthetic rubber, plastics, and pharmaceuticals. Benzene is found in gasoline and trace amounts are found in cigarette smoke. Benzene has been banned as an ingredient in products intended for use in the home, including toys. Benzene has a sweet, aromatic, gasoline-like odor. Most individuals can begin to smell benzene in air at 1.5 to 4.7 ppm.