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 is a water-soluble B vitamin vitamin B3 - and the common name for 2 very different compounds: nicotinic acid and niacinamide. High doses of niacin (as nicotinic acid) can lower cholesterol levels (although the exact mechanism of action is still not known).iacin is a water-soluble B vitamin vitamin B3 - and the common name for 2 very different compounds: nicotinic acid and niacinamide. High doses of niacin (as nicotinic acid) can lower cholesterol levels (although the exact mechanism of action is still not known).