Isoniazid, cycloserine, penicillamine: reduces the effect of pyridoxine.
Oral contraceptives: may decrease the plasma levels of pyridoxine.
Alcohol, hypnotics, sedatives or anxiolytics: may increase the action of these drugs.
Levodopa: pyridoxine reduces the effects of levodopa.
Nitrofurantoin: pyridoxine accelerates the renal excretion of nitrofurantoin. So, dosage adjustment of nitrofurantoin may be necessary.
Phenytoin: serum levels of phenytoin may be reduced.

It is contraindicated in patient with known hypersensitivity to this combination.

The side effects associated with the use of this combination be particularly caused by meclizine. There are allergies, blurred vision, dry mouth and fatigue.

There is no evidence of adverse effects of this combination on pregnancy or on the health of the fetus or neonate. But account should be taken with the use of antihistamines to just before the parturition. Pyridoxine is considered as safe in pregnancy. Pyridoxine is excreted in human milk but meclizine is unknown whether it is excreted or not. So, this combination may be indicated during lactation, if clearly needed.

Due to its anticholinergic action, this drug should be used with caution in patients with epilepsy, hyperthyroidism, severe heart failure, hypertension, glaucoma, prostatic hypertrophy, pyloric stenosis and bronchial asthma.

Keep in a dry place away from light and heat. Keep out of the reach of children.