Pyridoxine & Nausea

Pyridoxine is a one of several essential B vitamins and is sometimes called vitamin B-6. Most people get an ample supply of the vitamin in the foods they eat each day, and supplements may help with various medical conditions and ailments. When taken in supplement form, pyridoxine can cause side effects including nausea, although it also sometimes is recommended for treating nausea related to morning sickness. You should not take supplements such as pyridoxine during pregnancy unless you have first consulted with a doctor.

Pyridoxine for Morning Sickness

Women who suffer from severe nausea during pregnancy can benefit from taking a pyridoxine supplement to reduce the severity of the nausea and help limit episodes of vomiting, according to the results of a study published in the September 1995 issue of the "American Journal of Obstetrics and Gynecology." While the vitamin does appear helpful for women with severe nausea, it does not seem effective in those who have mild to moderate morning sickness, MedlinePlus reports. Despite its usefulness, you should not use pyridoxine to treat morning sickness without consulting with your doctor.

Recommended Dose

When used to treat morning sickness, standard dosing for pyridoxine is between 10 mg and 25 mg taken three to four times a day, MedlinePlus reports. For other medicinal uses, common doses include between 25 mg and 500 mg per day for kidney stones or between 50 mg and 100 mg per day to treat the symptoms of premenstrual syndrome. When used to address a vitamin B-6 deficiency, the standard dose is between 2.5 mg and 25 mg daily for three weeks, then a smaller dose to help maintain a proper level in the body, MedlinePlus reports. Always check with a doctor before taking pyridoxine so he can advise you of a safe and proper dose.

Side Effects

Most people who take pyridoxine supplements do so without experiencing any side effects, although some users do develop nausea, stomach pain, loss of appetite and abdominal pain, the University of Maryland Medical Center reports. Other known side effects include headaches, dizziness, a feeling of sleepiness, a tingling sensation and increased sensitivity to sunlight. Because of the potential for side effects, you should always consult with a medical practitioner before taking pyridoxine so you know what to expect.

Safety Precautions

Avoid taking pyridoxine in high doses because of potentially serious effects. In particular, high doses of the vitamin can cause nerve damage in the arms and legs, although the condition will reverse when you stop taking it, the National Institutes of Health Office of Dietary Supplements reports. Long-term use of high doses can cause brain and nerve problems. While pyridoxine is considered safe for use when pregnant and is sometimes used to treat morning sickness, you should only use it under the care of a doctor. While breastfeeding you should never exceed 2 mg per day -- the recommended dietary allowance -- because it can cause seizures in newborns.

Drug Interactions

In some cases, medications you take may interact with or interfere with pyridoxine supplements. You should not take pyroxidine with phenytoin because it decreases the effectiveness of the medication, MedlinePlus reports. Similarly, phenobarbital and levodopa can become less effective under certain circumstances when taken with the vitamin. Before taking pyridoxine, consult with a doctor or pharmacist who can advise you of any potential interactions with medications you take.