What types of tablets are there?
Tablets are solid, single-dose dosage forms containing one or more active ingredients as well as excipients, which are usually pressed from dry powders or granules under high pressure in special machines.
There are many different tablets, for example chewable, lozenge, effervescent and film-coated tablets. It is often important to take tablets with sufficient liquid. A glass of water is a good guideline.
Non-coated and coated tablets
In addition, there are tablets coated with different materials. These can be, for example, thin polymer coatings (film-coated tablets) or sugar coatings (coated tablets).
Effervescent tablets
These are non-coated tablets that dissolve rapidly after contact with water, releasing carbon dioxide. With the liquid, the active ingredient quickly enters the stomach and small intestine, resulting in a rapid onset of action.
Dissolving or dispersing tablets
Melting tablets
Lozenges are non-coated tablets that disintegrate rapidly in the mouth before being swallowed.
Lozenges and pastilles
These are tablets that release their active ingredient(s) slowly in the oral cavity when sucked. This is said to have either a local effect or – after absorption via the mucous membrane into the blood – a systemic effect (effective throughout the body).
Sublingual and buccal tablets
Tablets with altered release of active ingredient
Sometimes icht-coated tablets as well as film-coated tablets contain excipients that determine the speed, location or timing of the release of the active ingredient. In this way, the active ingredient can be released over a longer period of time (sustained-release tablet), delayed, or in a pulsatile manner.
Enteric-coated tablets
*In matrix tablets, the uniformly distributed active ingredient is embedded in a scaffold material (matrix). In some cases it is released from it through pores (heterogeneous porous matrix), in other cases it passes through the matrix material to the outside (homogeneous non-porous matrix). In addition, there are matrix tablets in which the active ingredient is released from a porous scaffold body (continuous matrix).
Chewable tablets
The advantage of chewable tablets is that the active ingredient is absorbed quickly and the effect sets in quickly. Certain excipients ensure that the chewable tablets taste pleasant.
Lyophilizate tablets
What are the different types of capsules?
Capsules are shaped hollow bodies of different sizes. They usually contain single-dose, solid active ingredients, but sometimes also pastes, viscous liquids or melt preparations. Capsules also refer to dosage forms in which the active ingredient is hermetically enclosed by gelatin or another suitable substance.
Hard capsules and soft capsules
Soft capsules are different, containing emollients (such as glycerol and sorbitol) in the capsule material.
Wafer capsules
These are usually made of rice flour and are briefly immersed in water before use: This causes the starch contained in the rice flour to swell, which makes it easier to take the wafer capsules.
This dosage form plays only a minor role today – among other things because it is costly to produce and susceptible to moisture.
These capsules contain excipients that determine the speed, location or timing of the release of the active ingredient. In this way, the active ingredient can be delivered over a longer period of time (sustained-release capsule), delayed or pulsed.
Enteric-coated capsules
These are delayed-release capsules that resist acidic stomach contents and dissolve only in the small intestine.
What types of powder are there?
Although powders are considered to be an independent dosage form, they are mostly used to prepare other dosage forms (e.g. capsules with powder contents).
Powder for ingestion
Powders are usually dissolved or suspended in water before ingestion. Effervescent components (such as hydrogen carbonates) may also be added for this purpose (= effervescent powder).
Powder for cutaneous use
What are the different types of granules?
Granules are produced by granulation (dry granulation, melt granulation, build-up granulation, etc.) of powders. Each granule is a construct of several powder particles that adhere together so tightly that further handling is possible. The surface of these granules is correspondingly porous.
Effervescent granules
These are non-coated granules that dissolve rapidly after contact with water, releasing carbon dioxide.
Direct granules
Granules that do not need to be dissolved in water before use are called direct granules. They are marketed in handy little bags that are emptied directly into the mouth as needed.
Coated granules
Such granules are coated with various materials, for example polymers.
Just like their counterparts from the group of tablets and capsules, these granules are coated with an enteric coating. This causes the granules to dissolve only in the small intestine.
Granules with modified release of active ingredient
These are coated or non-coated granules that contain excipients that determine the rate, location, or timing of drug release.
What are the different types of rectal preparations?
By far the most common form of rectalia are suppositories. There are also other solid, semi-solid and liquid rectalia.
Suppositories
Suppositories are single-dose, shape-retaining preparations that are inserted into the rectum. They usually have an elongated “torpedo” shape and melt at body temperature.
Rectal tampons
These are tampons containing active ingredients that are designed to remain in the lower part of the rectum for a certain period of time. Often, these rectal tampons are suppository-like preparations that contain a mullein insert for better local fixation.
Rectal capsules
Rectal solutions and suspensions
These enemas are used for local treatment (e.g., in chronic inflammatory bowel disease) or as a laxative. The solutions or suspensions are either already packaged in ready-to-use bags or bottles or are freshly prepared by dissolving solid dosage forms such as tablets or powders before use.
Rectal foams
Rectal foams are foams containing active ingredients for rectal use. They are used in a similar way to an enema.
Semi-solid preparations for rectal application
Rectalia also include ointments, creams and gels that are applied rectally with or without an applicator. To ensure that the active ingredients are better absorbed, such preparations are usually lipophilic (fat-soluble).
What are the different types of vaginal preparations?
Vaginal suppositories
In contrast to suppositories, vaginal suppositories have an egg-shaped form (“ovules”). The two dosage forms also differ in mass, which for vaginal suppositories is between two and six grams.
To ensure even wetting of the vaginal mucosa, vaginal suppositories usually consist of a macrogol mass that is poured into special molds similar to suppositories.
Vaginal tablets
Vaginal capsules
Soft gelatin capsules, the shape of which is adapted to vaginal use, are used as vaginal capsules.
Vaginal tampons
They are made of absorbent cotton or gauze containing active ingredients or cellulose containing active ingredients. However, this form of vaginal preparations hardly plays a role in practice.
Semi-solid preparations for vaginal use
Vaginal foams
They are introduced into the vagina via a pressurized gas pack with special valves and an applicator for insertion. Here, the active ingredient is dissolved in an emulsion, which is transformed into a foam with the aid of propellant gas and surface-active excipients.
Solutions, suspensions and emulsions for vaginal use
What are the different types of semi-solid preparations?
Semi-solid preparations for cutaneous use are colloquially known as “ointments”. They are spreadable dosage forms for use on healthy, diseased or injured skin. The active ingredients incorporated can be either dissolved (solution ointments) or suspended (suspension ointments).
Ointment
Ointments are anhydrous preparations made from a uniform (single-phase) base. Depending on their properties, a distinction is made between hydrophobic ointments (“water-avoiding”, can only absorb small amounts of water), hydrophilic ointments (“water-loving”, can absorb larger amounts of water) and water-absorbing (miscible with water) ointments.
Cream
A distinction is made between lipophilic (“fat-loving”), hydrophilic (“water-loving”) and amphiphilic (“fat and water-loving”) creams.
Gel
Gels are liquids that are gelled with the aid of a suitable gelling agent. As a rule, this refers to hydrophilic gels in which water gels to form a spreadable mass with the addition of gelling agents such as cellulose or carbomers.
Paste
Pastes contain large proportions of finely divided powders in their base. The higher the powder content, the thicker and harder the paste.
The pharmacopoeia does not define precisely when a paste is no longer an ointment, but is instead considered a paste. Normally, ointments with a solids content of at least 20 percent are referred to as pastes.
Envelope paste
What are the types of oral liquids?
Oral liquids are divided into solutions, emulsions, suspensions, drops and syrups.
Oral solutions
A solution is a liquid medicine that contains active ingredients and excipients in dissolved form, making them easy to swallow. Solutions are especially suitable for small children and patients with swallowing problems.
There are also solutions for external use (e.g. on the gums).
Emulsions are systems consisting of two or more immiscible liquids (e.g. oil in water). Emulsions can be stabilized for a limited period by adding emulsifiers.
However, they always show a tendency to phase separation, which is why they must be shaken up before each application. This allows uniform distribution and thus dosage to be ensured.
There are also emulsions for external use, for example in the form of a skin cream.
Suspensions are liquid preparations in which solid particles are distributed – but not dissolved. Similar to emulsions, they show a strong tendency to phase separation (sinking of the solid particles to the bottom), which is why they must be shaken up before each application. As with emulsions, this is to ensure uniform distribution of the particles contained and thus the correct dosage.
Drops for oral use
Drops are liquid medicines that are filled into a dropper bottle. With the aid of a dropper or pipette, the active ingredient can be dosed individually.
Syrups
A syrup is a viscous, sweet-tasting, aqueous liquid. Classic syrups consist of a sugar-water mixture. Newer sugar-free variants contain various gelling agents and sweeteners or sugar substitutes such as sorbitol.
These are ready-made and pre-dosed powders or granules that can be used to prepare solutions or suspensions for ingestion by adding water. A well-known example is antibiotic dry juices.
Powder for the preparation of oral drops
There are also ready-made and pre-dosed powders, with the help of which oral drops can be prepared by adding water.
What are the different types of chewing gum?
What are the different types of plasters?
Plasters are flexible, adhesive preparations intended for external use.
Plasters without active ingredients
Small wounds such as abrasions or the puncture site after blood collection are covered with a conventional plaster that does not contain active ingredients.
Plasters containing active ingredients
Transdermal patches
They are also called transdermal therapeutic systems (TTS). The difference between these and patches containing active ingredients is that TTS release the active ingredient into the bloodstream, which makes it possible to achieve a systemic effect (e.g. pain patches, contraceptive patches).
What are the different types of parenteral preparations?
These forms of preparation can be introduced, for example, under the skin (subcutaneous, s.c.), into a muscle (intramuscular, i.m.) or into a vein (intravenous, i.v.). This is advantageous for active ingredients that would dissolve in the gastrointestinal tract or cannot be absorbed through the intestinal mucosa (e.g. proteins, larger active ingredient molecules, unstable drugs).
The disadvantages are the high costs and the strict requirements for sterility of the preparations: since they are administered directly into the bloodstream, parenterals must meet strict requirements for sterility, which can only be met in special production facilities set up for this purpose.
Injection preparations
Infusion preparations
These are also sterile aqueous or oily preparations (solutions, emulsions or suspensions). However, they are not administered by syringe, but by infusion. And the amount administered is much larger than with an injection.
Concentrates
Powder
Similar to concentrates, sterile powders can be used to prepare an injection or infusion preparation by adding a suitable sterile liquid.
Prefilled syringes
What are the different types of inhalers?
Inhalers are aids for inhaling medicinal substances. Inhalanda (the active ingredients for inhalation) can be either dissolved in water or in the form of a dry suspension. Thus, they are liquid or solid dosage forms that are applied as vapor, aerosol, or powder in the respiratory tract to achieve a local or systemic effect.
Metered dose inhalers
When the metered dose inhaler is actuated, part of the solution (or suspension) escapes. This causes the liquid to evaporate explosively – the active ingredient is finely dispersed. The resulting aerosol cloud leaves the MDI at high speed.
To prevent a large proportion of the active ingredient from hitting the pharyngeal wall and being swallowed ineffectively, patients must coordinate their inhalation maneuver precisely with the triggering of the MDI.
Powder inhalers
Powder inhalers (dry powder inhalers; DPI) contain the active ingredient in the form of a powder which is automatically atomized by the force of the airflow during inhalation and enters the lungs. The powder can either be “reloaded” individually as a capsule (capsule inhaler) or be in the form of a so-called multi-dose system (e.g. discus, turbo inhaler).
Correct handling should be checked regularly by a doctor or pharmacist.
Dual jet inhalers
This type of inhaler is somewhere between a nebulizer and a metered-dose inhaler. This is due on the one hand to the fact that the aerosol cloud produced is comparatively slow and long-lasting (cf. nebulizer), and on the other hand to the handiness of the device (cf. metered dose inhaler).
Correct handling should be checked regularly by a doctor or pharmacist.
Nebulizers
These are stationary devices powered by electricity that use ultrasound or compressed air to atomize and continuously release the contained liquid. The particle size as well as their speed are extremely advantageous for inhalation. However, due to the low concentration of active ingredient per breath, an inhalation period of ten to 20 minutes is required.
What are the preparations for application to the eye?
Preparations for application to the eye are called ocularia. Their therapeutic effect is usually localized to the eye or adjacent tissue. There are special requirements with regard to their sterility.
Eye drops
Sterile, liquid preparations for application to the eye are called eye drops. They have a limited shelf life after opening. A distinction is made between aqueous and oily eye drops.
- Sterility
- Clarity
- Preservation
- Stability
- pH value
- Viscosity
In oily eye drops, the contact time of the active ingredients on the eye is prolonged, which may be desirable. And the oily drops have to meet significantly fewer conditions than the aqueous ones. Consequently, they are easier to prepare. Last but not least, some active ingredients can only be used in the form of oily preparations.
However, the oily consistency temporarily impairs vision.
Eye baths
Eye baths are sterile, aqueous solutions used to rinse the eye or to soak eye compresses. This is mainly done after injuries, burns or burns in the eye area.
Eye baths have a limited shelf life after opening.
Powder
It is also possible to prepare eye drops and agent baths from a powder. These powders form a separate category in the European Pharmacopoeia.
Semi-solid preparations
The application temporarily impairs vision.
Anyone who needs additional eye drops should apply these first and only then apply the eye ointment.
Eye inserts
Eye inserts are sterile, solid or semi-solid preparations for application in the conjunctival sac. Here, the embedded active ingredient is released with a time delay via a special matrix. There are biodegradable and non-biodegradable systems.
What preparations are available for application to the ear?
If the preparations are to be used in the event of a tear or hole in the eardrum (eardrum perforation) or before and after a surgical procedure on the ear, they must be sterile, unpreserved and filled in sterile single-dose containers.
Ear drops and ear sprays
Ear drops and ear sprays are suspensions, emulsions or solutions in suitable liquids (e.g. glycerol, water, fatty oils) which are introduced into the external auditory canal.
Ointments and creams are available as semi-solid preparations for application to the ear. They are applied to the external auditory canal with an enclosed applicator.
Ear powders, rinses and tampons
Ear powders are also applied to the external auditory canal with a suitable applicator.
Ear rinses are aqueous solutions used to clean the external auditory canal.
Medical tampons are used as ear tampons. They are placed in the external auditory canal.
Preparations for use in the nasal cavities (= nasalia) are liquid, semi-solid or solid preparations containing one or more active ingredients. They are intended to achieve either a local or a systemic effect.
Nasal drops and nasal sprays
There are various solutions, emulsions or suspensions for dripping or spraying into the nasal cavities. Nasal sprays can be marketed in containers with a spray device or pressurized containers.
An enclosed applicator can be used to apply ointments and creams to the nasal cavities.
Nasal powder
These are powders containing active ingredients, which are blown into the nasal cavities with a suitable applicator.
Nasal rinses
Aqueous solutions are used as nasal rinses. They are used to clean the nasal cavities.
Nasal rinses
What are the types of preparations for use in the oral cavity?
Preparations for use in the oral cavity are liquid, semisolid or solid preparations that can achieve a local or systemic effect.
Gargle solutions
Mouthwashes
Mouthwashes are also aqueous solutions with a mostly neutral pH value. They are used to rinse the mucous membrane of the oral cavity and then swallowed (mouthwashes must not be swallowed!). Mouthwashes can also be in ready-to-use form or made from tablets, concentrates and powders.
Solutions for application to the gums
They are applied to the gums using a suitable applicator.
Both preparations are applied to the mucous membranes of the oral cavity using a suitable applicator. Suspensions, however, must be shaken before use.
Semi-solid preparations for application in the oral cavity
They are available in the form of hydrophilic gels or pastes and are applied to the oral cavity or gums. They are offered in multi-dose and single-dose containers.
Sprays
Lozenges and pastilles
These are single-dose preparations that are sucked for the purpose of a local effect and dissolve slowly. Lozenges are pressed like normal tablets, pastilles are poured into molds like suppositories and packaged after hardening.
Capsules for use in the oral cavity
Mostly soft capsules that are either chewed or sucked.
Mucoadhesive preparations
What are the special dosage forms?
Medicinal baths
Medicinal baths contain various ingredients such as fats, essential oils, organic compounds (e.g., sulfur), sea salt, plant extracts, and/or tannins. The bath additives are used for full or partial baths.
Shampoos
Active ingredient-containing foams
Active ingredient-containing foams are preparations in which a large volume of Gs is dispersed in a liquid phase. The addition of a surface-active substance ensures the stability of the resulting foam. Foams for use on open wounds or severely damaged skin must be sterile.