Vitamin B1 (thiamine) is an essential coenzyme in carbohydrate metabolism by combining with ATP to form thiamine pyrophosphate . Vitamin B2 (riboflavin) is a component of flavoprotein enzymes that work together , which are necessary for normal tissue respiration ; also needed for activation of pyridoxine and conversion of tryptophan to niacin.
Vitamin B6 (pyridoxine) is a precursor to pyridoxal , which functions in the metabolism of protein , carbohydrates , and fats ; pyridoxal also aids in the release of liver and muscle – stored glycogen and in the synthesis of GABA (within CNS) and heme.
Nicotinamide (niacinamide) is used by the body as a source of niacin ; is a component of two coenzymes (NAD and NADP) which is necessary for tissue respiration , lipid metabolism , and glycogenolysis ; inhibits the synthesis of very low density lipoproteins ; dose not have hypolipidemia or vasodilating effects.
Dexpanthenol is a pantothenic acid B vitamin alcohol analog , that is converted to coenzyme A internally ; coenzyme A is essential to normal fatty acid synthesis , amino acid synthesis and acetylation of choline in the production of the neurotransmitter , acetylcholine.

Vitamin B deficiency (prophylaxis and treatment) . This vitamin supplement is also indicated in : Elderly patients to improve their disease ; concurrent with broad – spectrum antibiotics after surgery.

Vitamin B1: Cardiovascular collapse ; Paresthesia
Vitamin B2: Discoloration of urine (yellow – orange )
Vitamin B6: Headache ; Sensory neuropathy ; Decreased serum folic acid ; Nausea ; Increased AST ; Paresthesia ; Allergic reactions.
Nicotinamide: Tachycardia ; Increased sebaceous gland activity ; Rash ; Bloating ; Flatulence ; Nausea ; Paresthesia ; Blurred vision ; Wheezing .
Dexpanthenol: Slight drop in blood pressure ; Agitation ; Dermatitis ; Irritation ; Itching ; Urticaria ; Diarrhea ; Hyperperistalsis ; Vomiting ; Paresthesia ; Dyspnea ; Allergic reactions .

Nicotinamide: Hypersensitivity to niacin , niacinamide ; Liver disease ; Active peptic ulcer ; Severe hypotension ; Arterial hemorrhage
Dexpanthenol: Hypersensitivity to dexpanthenol ; Mechanical obstruction of ileus.
Other components: Hypersensitivity to vitamin B1 , vitamin B2 , vitamin B6 or any component of the formulation .

Vitamin B6: Dependence and withdrawal may occur with doses > 200 mg/day.
Nicotinamide: Use caution in heavy ethanol users , unstable angina or CAD , diabetes , renal disease , active gallbladder disease , gout .
Dexpanthenol: Avoid drugs which decrease motility .

Vitamin B1: Neuromuscular blocking agents , high carbohydrate or IV dextrose increase thiamine requirement .
Vitamin B2: Probenecid decreases absorption of vitamin B2.
Vitamin B6: It decreases serum levels of levodopa , phenobarbital and phenytoin.
Nicotinamide: The effect of oral hypoglycemic drug may be decreased by niacin . Niacin may inhibit uricosuric effects of sulfinpyrazone and probenecid . Aspirin decreases adverse effect of flushing . The risk of toxicity (myopathy) of lovastatin is increased . Concurrent use of adrenergic blocking agents with nicotinamide has additive vasodilating effect and postural hypotension.

Vitamin B complex syrup may be taken with food to decrease stomach upset.

• Prophylaxis: Usual adult dose: 1-3 teaspoonfuls per day.
• Usual pediatric dose: 1-2 teaspoonfuls per day.
• Usual geriatric dose: Initial : Oral , 1.25 to 2.5 mg a day with breakfast , with dosage changes being made by no more than 2.5 mg at weekly intervals if needed.
• Treatment: Treatment dose is individualized by prescriber based on severity of deficiency.

• USP DI, 2004
• Up To Date, Vol. 13.1 (2005)
• Martindale, The Complete Drug Reference, 33 rd edition 2002