 [ Symptoms ] can i take benadryl while taking propranolol 20 mg [ Disease ] hi dear chap you should find that missing just one pill is not as bad as you think but she did double up she should be ok and so should you look if so worried about her getting pregnant keep her on the pill as this does regulate her periods and you wear condoms its called being double safe chuck in some spermicide your be on triple protection doohope this calms the nerves good luck