Supplier Irons & Vitamins , Oral jelly, Tablets and Capsule

Many multivitamins are formulated and/or labeled to differentiate consumer sectors e.g. prenatal, children, mature or 50+, men's, women's, diabetic, stress or megavitamin. Consumer multivitamin formulas are available as tablets, capsules, bulk powder, or liquid. Once and twice per day multivitamin formulas dominate common usage, although some formulas are designed for consumption 3–7 times per day or even allow hourly use.

Compositional variation amongst brands and lines allows substantial consumer choices. Modern multivitamin products roughly classify into RDA centric multivitamins with or without iron, RDA centric multivitamin/multimineral formulas with or without iron, higher potency formulas with mostly above RDA components with or without iron, and more specialized formulas by condition, such as for diabetics or by less common components, such as diversified antioxidants, herbal extracts or premium vitamin and mineral forms. Legally, the US FDA allows a multivitamin to be called "high potency" if at least two-thirds of its nutrients have at least 100 percent of the DV. In practice, "high potency" usually means substantially increased vitamin C and Bs with some other enhanced vitamin and mineral levels, but some minerals may still be much less than DV.

By supplementing the diet with additional vitamins and minerals, multivitamins can be a valuable tool for those with dietary imbalances or different nutritional needs. People with dietary imbalances may include those on restrictive diets and those who can't or won't eat a nutritious diet. Pregnant women and elderly adults have different nutritional needs than other adults, and a multivitamin may be indicated by their physicians.

The proponents of orthomolecular medicine recommend individually optimized vitamin intakes, usually at higher doses than standard recommendations (such as the US RDA). They also recommend more absorbable forms of vitamins and minerals, in inexpensive but higher potency formulas, spread across the day.

While multivitamins can be a valuable tool to correct dietary imbalances, it is worth exercising basic caution before taking them, especially if any medical conditions exist. In particular, pregnant women should generally consult their doctors before taking any multivitamins: for example, either an excess or deficiency of vitamin A can cause birth defects.[6] Some analyses have suggested that long-term use of beta-carotene, vitamin A, and vitamin E supplements may shorten life rather than extend it, with the additional risk being particularly large in smokers.

Severe vitamin and mineral deficiencies require medical treatment and can be very difficult to treat with common over-the-counter multivitamins. In such situations, special vitamin or mineral forms with much higher potencies are available, either as individual components or as specialized formulations, sometimes requiring a prescription.

Multivitamins in large quantities may pose a risk of an acute overdose, due to the toxicity of some components, principally iron. However, in contrast to iron tablets, which can be lethal to children, toxicity from overdoses of multivitamins are very rare. There appears to be little risk to supplement users of experiencing acute side effects due to excessive intakes of micronutrients. There also are strict limits on the retinol content for vitamin A during pregnancies that are specifically addressed by prenatal formulas. Additionally, various medical conditions and medications may adversely interact with multivitamins.

For normal adults taking a multivitamin for general health purposes, it is recommend that a multivitamin should contain 100% DRI/RDA or less for each ingredient.[citation needed] However, many common brand supplements in the United States contain above-DRI amounts for some vitamins or minerals. Many brands offer low iron or iron-free versions of their multivitamin supplements.