Pharmaceutical Elixirs

The USP XVII defines elixirs as clear, sweetened hydroalcohol liquids intended for oral use containing flavoring substances or active medicinal agents. Their primary solvents are alcohol and water, with glycerin, sorbitol and syrup sometimes as an additional solvent and/or sweetening agents. They are prepared by simple solution or admixture of the several ingredients. They are used either as vehicles or for the therapeutic effect of the medicinal substances that they contain.

According to their definition, elixirs are divided into two groups:

1. Flavored Elixirs
   It is used for flavor and vehicles in prescriptions.
2. Medicated Elixirs
3. It is used for the therapeutic effect or property of the medicinally active agent or as vehicle for other drugs.

Elixirs contain ethyl alcohol. However, the alcoholic content will vary greatly, from elixirs containing only small quantity to those that contain a considerable portions as a necessary aid to solubility. Elixir may also contain glycerin and syrups which may be added to increase solubility of the medicinal agent or for sweetening purposes. Some elixirs contain propylene glycol and some claim that this solvent is satisfactory substitute for both glycerin and alcohol. Although alcohol is an excellent solvent for some drugs, it does accentuate the saline taste of bromides and similar salts. Therefore, it is often desirable to substitute some other solvent that is alcohol in the formula. If taste is a consideration, the formulation is more prone to utilize a syrupy rather than a hydroalcoholic vehicle.

Elixir containing water and alcohol-soluble ingredients may be prepared as follows:

Dissolve the water-soluble ingredients in part of the water, add and dissolve the sucrose in it. Dissolve the other ingredients in the alcohol. Add the aqueous phase to the alcoholic solution, filter and make the necessary volume by adding water.

Sucrose increases viscosity but decreases the solubility properties of water and so must be added after primary solution has been carried out.

A high alcoholic content is maintained during preparation by adding aqueous phase to the alcoholic solution. Elixirs should be brilliantly clear and therefore strained or filtered, if necessary, subjected to clarifying action of purified talc or siliceous earth.

Elixirs contain alcohol thus incompatible or precipitate tragacanth, acacia, and agar from aqueous solutions, inorganic salts from similar solutions. So such substances should be absent form the aqueous phase or should be present in such concentrations that there is no danger of precipitating on standing.

Aqueous solutions added to elixir will cause a partial precipitation of ingredients due to the reduced alcohol content of the final preparation. Usually, however, the alcohol content of the mixture is not sufficiently high to cause separation. As vehicle for tinctures and fluidextracts, the elixirs generally cause a separation of extractive matters from these products due to a reduction of the alcoholic content.