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.
Niacin supplements are available as nicotinamide or nicotinic acid. Nicotinamide is the form of niacin typically used in nutritional supplements and in food fortification. Niacin is available over the counter and with a prescription as a cholesterol-lowering agent (84) .