
Effervescent or carbon tablets are tablets which are designed to dissolve in water, and release
carbon dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...
. They are products of
compression of component ingredients in the form of powders into a dense mass, which is packaged in
blister pack
A blister pack is any of several types of pre-formed plastic packaging used for small consumer goods, foods, and for pharmaceuticals.
The primary component of a blister pack is a cavity or pocket made from a formable web, usually a thermofor ...
, or with a
hermetically sealed package with incorporated
desiccant
A desiccant is a hygroscopic substance that is used to induce or sustain a state of dryness (desiccation) in its vicinity; it is the opposite of a humectant. Commonly encountered pre-packaged desiccants are solids that absorb water. Desiccants ...
in the cap. To use them, they are dropped into water to make a
solution. The powdered ingredients are also packaged and sold as effervescent powders or may be granulated and sold as effervescent granules. Generally powdered ingredients are first granularized before being made into tablets.
Effervescent medicinal beverages date back to the late 1800s and originally arose to mask the taste of bitter waters taken as curatives, during the
water cure Water cure may refer to:
* Water cure (therapy), a course of medical treatment by hydrotherapy
* Water cure (torture), a form of torture in which a person is forced to drink large quantities of water
* ''The Water Cure
''The Water Cure'' is ...
craze of that era.
History
In the 17th and 18th centuries, scientists began uncovering the chemical make-up and physiological benefits of various salts such as
Glauber's salt
Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 mill ...
and
Epsom salts
Magnesium sulfate or magnesium sulphate (in English-speaking countries other than the US) is a chemical compound, a salt with the formula , consisting of magnesium cations (20.19% by mass) and sulfate anions . It is a white crystalline solid, ...
.
These salts were found in mineral springs, which, since the
Roman Empire
The Roman Empire ( la, Imperium Romanum ; grc-gre, Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) was the post- Republican period of ancient Rome. As a polity, it included large territorial holdings around the Medite ...
, had been used as health
spa
A spa is a location where mineral-rich spring water (and sometimes seawater) is used to give medicinal baths. Spa towns or spa resorts (including hot springs resorts) typically offer various health treatments, which are also known as balneothe ...
s, where people would go to bathe in, and drink, mineral-rich waters for their health. These developments led to attempts to replicate the salt mixtures found in these naturally occurring
mineral waters using off-the-shelf ingredients.
Mixing these kinds of salts — especially
carbonates
A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate ...
and
tartrates — with flavorings like lemon into an effervescent compound with citric or tartaric acid proved especially popular and set off a craze for the new "fruit salts". Effervescent tablets have been used as products of the pharmaceutical and dietary industries for over two centuries.
Use
In by-mouth medicine
Vitamins may be sold as effervescent tablets.
There are several categories of active ingredients that may be best administered in the form of effervescent preparations:
# Those that are difficult to
digest
Digest may refer to:
Biology
*Digestion of food
*Restriction digest
Literature and publications
*''The Digest'', formerly the English and Empire Digest
*Digest size magazine format
* ''Digest'' (Roman law), also known as ''Pandects'', a digest ...
or disruptive to the stomach or esophagus
# Those that are
pH–sensitive, such as
amino acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha ...
s and
antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy, ...
s.
# Those requiring a large dose.
# Those that are susceptible to light,
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as we ...
, or
moisture
Moisture is the presence of a liquid, especially water, often in trace amounts. Small amounts of water may be found, for example, in the air (humidity), in foods, and in some commercial products. Moisture also refers to the amount of water vapo ...
.
# It is used as a gastrointestinal agent.
Effervescent preparations may enhance absorption and speed up onset of action by increasing
gastric
The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach i ...
pH, therefore hastening the emptying of medication into the small intestine. The carbon dioxide bubbles may also help intestinal absorption by opening up
paracellular transport
Paracellular transport refers to the transfer of substances across an epithelium by passing through the intercellular space ''between'' the cells. It is in contrast to transcellular transport, where the substances travel ''through'' the cell, pa ...
. Extreme
bioavailability
In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation.
By definition, when a medication is administered intravenously, its bioavailability is 100%. ...
differences of up to 4-fold have been reported comparing effervescent tablets with ordinary tablets, highlighting the need for extra
bioequivalence
Bioequivalence is a term in pharmacokinetics used to assess the expected in vivo biological equivalence of two proprietary preparations of a drug. If two products are said to be bioequivalent it means that they would be expected to be, for all ...
studies when switching dosage forms.
It is dangerous to swallow an effervescent tablet directly, as the tablet can get stuck in the
subglottis and fizzle there. A potentially fatal
edema
Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels tight, the area ma ...
may occur from the irritation. In addition, conventional effervescent tablets contain a significant amount of
sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable ...
and are associated with increased odds of adverse cardiovascular events according to an 2013 study. Low or no-sodium formulations exist.
Other
"Cleaning tablets" are formulations carrying
detergent
A detergent is a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions. There are a large variety of detergents, a common family being the alkylbenzene sulfonates, which are soap-like compounds that are m ...
s for cleaning. They may be used in
laundry
Laundry refers to the washing of clothing and other textiles, and, more broadly, their drying and ironing as well. Laundry has been part of history since humans began to wear clothes, so the methods by which different cultures have dealt with t ...
, in cleaning of specific machines or containers, in cleaning of dentures and
contact lenses
Contact lenses, or simply contacts, are thin lenses placed directly on the surface of the eyes. Contact lenses are ocular prosthetic devices used by over 150 million people worldwide, and they can be worn to correct vision or for cosmetic ...
, etc.
Some tablets used for dyeing eggs for Easter are effervescent.
There also exist effervescent tablets for making soda.
Capsules
Effervescent tablets mostly come in capsules constructed for these tablets. They may contain an anti-bacterial coating and are water resistant. The cap contains a little spring-like spiral, which helps keeping the tablets in place during transportation and prevents them from breaking. The cap also contains little balls made out of
silica gel
Silica gel is an amorphous and porous form of silicon dioxide (silica), consisting of an irregular tridimensional framework of alternating silicon and oxygen atoms with nanometer-scale voids and pores. The voids may contain water or some other ...
.
They sit after a little piece of cardboard and make sure no moisture comes into contact with the tablets.
See also
*
Sherbet (powder), effervescent powder for drinks
References
*
*
* .
{{Authority control
Dosage forms