The majority of pregnant women do not complain of morning sickness until the 6th week of pregnancy, 2 weeks after a missed period. But for some women, that nagging feeling can start as early as one week after conception, a full week before a missed period. Changes in hormones account for the queasiness that occurs.
DRUG CLASS AND MECHANISM: Niacin (nicotinic acid, vitamin B3) is a part of the normal diet that is essential to various chemical reactions in the body.
Basic Description. Niacin is a blanket term for a family of compounds with vitamin B3 activity. The terms niacin and vitamin B3 can be used interchangeably, and whenever you find either term on our website, we are referring to the same group of compounds. Basic types of vitamin B3 include nicotinamide, nicotinic acid, and several active enzymatic forms, each of which can be obtained from food.