How much Benadryl can you take in pregnancy? Doctors usually recommend taking a 25mg to 50mg oral dose once every six hours [11] in the first trimester, while the dosage should not generally exceed 25mg in six hours during the last two trimesters [6, 7]. Use of topical Benadryl is considered safe in pregnancy as there is little evidence of harm to the fetus. However, there is inadequate data regarding whether the diphenhydramine in the ointment form crosses the placenta [5].
Best Answer: Mutagen: a substance that causes mutation, i.e. that causes changes in genes. Teratogen: Substance that deforms the fetus in the womb and so induces birth defects. Carcinogen: a substance that causes cancer. All of them give undesirable defects in human beings, the difference is obvious from the definitions.
A carcinogen is a substance that is capable of causing cancer in humans or animals. If a substance is known to promote or aggravate cancer, but not necessarily cause cancer, it may also be called a carcinogen. Though there are many things that are believed to cause cancer, a substance is only considered carcinogenic if there is significant evidence of its carcinogenicity. A carcinogen may act on deoxyribonucleic acid (DNA), causing dangerous changes, or it may work to increase the rate of cell division.