It should be noted that the ingredients used in tablet effervescent should have the contents moist very low and when the manufacture of this preparation must be done in a dry place.

Characteristic of Effervescent tablet ingredients:

1. In many ways, the principles used in producing Effervescent tablets similar to those used for conventional tablets. Many of the processes and tools the same process. Likewise, the general nature of granules required for obtaining tablets according to the requirements such as:
  • Particle Size
  • Particle shape
  • Granulometri
  • Uniformity of distribution
  • Free flow of granules
  • Granules must be compressed

2. The nature of raw materials selected for use in Effervescent Tablets that more important than tablets conventional is the moisture content, which means the raw materials used must be dry.
If the raw material used is not dry (containing moisture), then acid reaction will occur the carbonate will cause the product to be physically unstable and decompose. Once started the reaction it will continue much faster because the byproducts reaction is water added.

CH2COOH + 3NaHCO3 CHCOONa + 3 CO2 + 3 H2O

Therefore, the raw materials used must be in anhydrous (dry) with a few levels humid absorbed. The water molecule is still there but very little because it takes a little water to bind the granules because if the granules too dry, granules can not be compressed.

3. Solubility is the nature of the raw materials that are important in Effervescent Tablets. If the components of the tablet does not dissolve, the Effervescent reaction will not happen and tablets will not be disintegrated rapidly. The speed of dissolving is more important than the solubility due to substances that dissolve slowly to impede disintegration of tablets and dissolve slowly to produce residue that is not favored after tablet disintegration.

Sources of Carbon Dioxide
Sources of carbon dioxide from Effervescent Tablets obtained from carbonate salts because this salt to generate 53% carbon dioxide. Salt is often used is sodium bicarbonate and sodium carbonate. Sodium bicarbonate with a concentration in water 0.85% showed pH 8.3. sodium carbonate with a concentration of 1% in water has a pH of 11.5. Sodium carbonate shows also the effect of stabilization in Effervescent Tablets for its ability to absorb moisture in advance can prevent the onset response Effervescent. Oxygen can be a source of Effervescent with sources can be used sodium perborates anhydrous.

Acid Source
Source of acid commonly used in Effervescent Tablets can be classified into;
a. Acid Foods, among others:
  1. Citric acid, an acid used most often because the price is cheap. Citric acid can dissolve easily and quickly, and in the form of granules can flow freely. There is also a form of anhydrate form, and it’s hygroscopic. 
  2. Tartaric acid, this acid has a solubility of higher than of citric acid.
b. Anhydrous Acid
If the acid anhydride is dissolved in the water there will be a liberating form of acid hydrolysis which can react with carbon dioxide source. Example : succinic anhydride.

c. Acid Salt
This salt can be used because in solution, this salt can produce protons and produce a solution with a pH below 7. Examples : sodium hydrogen phosphate, sodium dihydrogen phosphate, and sodium bisulfite.

Other Ingredients for Effervescent Tablet
Other additives in Effervescent Tablets, among others, such as binders, fillers, and lubricants. However, these materials use in limited amounts. As with any filler, only used a little, because the formula Effervescent Tablets already contains a lot of carbonate and acid.

a.Binder and Wetting agent
To manufacture Effervescent Tablets with the method of granulation using, a binder such as gelatin, starch and gums can not be used because the solubility is slow or because the content of residual water is high that can accelerate the instability of Effervescent Tablets. Effective binder for Effervescent Tablets is PVP. PVP added to the powder which is granulated in a dry state and then wetted by wetting agent, isopropanol, ethanol or hydro-alkohol. Alcohol is not binding but added as wetting agent to dissolve PVP.

b. Filler
Usually, it takes only a little filler because substance that produces effervescent already quite large. Sodium bicarbonate is a good filler. Other fillers are Na. Chloride, Na. Sulfate and Na. Bicarbonate.

c. Lubricants
Lubricants that are water soluble or substance that can be dispersed in water can be used as a lubricant. Powder of sodium benzoate and PEG 8000 is an effective, water soluble lubricant.