Unisom And B6 Dosage For Pregnancy is often used together to help relieve nausea during pregnancy. A common dosage recommendation is 25 mg of Vitamin B6 (pyridoxine) taken up to three times a day, paired with 12.5 mg of Unisom (doxylamine) taken once or twice daily. It’s essential to consult a healthcare provider before starting this combination to ensure safety and proper dosage based on individual needs and medical history.