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Using medication: Oral medications

Created: ; Last Update: August 10, 2017; Next update: 2020.

Many different medications are taken orally (by mouth). They come as solid tablets, capsules, chewable tablets or lozenges to be swallowed whole or sucked on, or as drinkable liquids such as drops, syrups or solutions.

In most cases, the ingredients in oral medication don't enter the bloodstream until they reach the stomach or bowel. Sometimes the drug is absorbed by the lining of the mouth, like is the case with lozenges. Some active ingredients – for example, certain laxatives or contrast agents – aren't meant to enter the bloodstream in large quantities at all.


Tablets are available in many different shapes and sizes. They are simple to manufacture and can keep for a long time. One or more active ingredients are combined with so-called excipients (carrier substances that help hold the tablet together) and then pressed into tablet form.

  • Tablets without coating: These tablets are made of powder or granulate pressed tightly together. If they're not given a coating, they usually have a dull surface. It is important to take tablets with water to avoid them getting stuck in your food pipe, and so that there is enough liquid in your stomach to allow the tablet to dissolve.
  • Coated tablets (sugar-coated or film-coated tablets): Tablets can be covered with a layer to protect them against external influences, such as dampness or bacteria. Coated tablets are smooth, colored, and often shiny. They go down easier when you swallow and are tasteless. Depending on what the coating is made of and how thick it is, people differentiate between sugar-coated and film-coated tablets. Sugar-coated tablets are usually round or oval in shape; film-coated tablets only have a thin coating. If tablets contain active ingredients that have to be protected from the acid in the stomach, they are coated with a protective layer that is resistant to gastric acid (gastro-resistant). Then the active ingredients are not released until they reach the small intestine. Coated tablets should not be crushed or chewed because then they will no longer be protected by the coating.
  • Fizzy tablets: Fizzy (effervescent) tablets are dissolved in a glass of water for drinking. They are well suited for people who have difficulty swallowing, and can have a faster effect than tablets because the medication has already dissolved by the time it arrives in the stomach.
  • Chewable tablets and lozenges: These contain active ingredients that are intended to have an effect in the throat, for example for a sore throat, or that can be absorbed through the lining of the mouth. These tablets are either chewed or sucked on.
  • Buccal tablets (from the Latin bucca meaning "cheek”), sublingual tablets (from the Latin sub meaning "under" and lingua meaning "tongue"): These soluble tablets are placed into a cheek pouch or under the tongue to let them slowly dissolve. The active ingredient is absorbed into the bloodstream directly through the lining of the mouth and spread through the rest of the body.

Capsules and chewable capsules

Capsules have a shell – usually made of gelatin – containing the medication in the form of a powder, granulate or liquid. The shell dissolves in the stomach or bowel and then releases the active ingredient. Capsules are long-lasting and tasteless, and even sensitive active ingredients keep well in capsules. There are also chewable capsules that you bite into so that the active ingredient can be absorbed through the lining of the mouth.

Time-release tablets and capsules

Time-release (sustained-release) tablets and capsules are designed to release their active ingredients slowly. A time-release tablet may contain an entire day’s worth of the active ingredient, and then release it evenly over the course of the day. This has the advantage that only one tablet is needed per day, and not several.

Powders, drops and granulates

Powders and granulates

Some drugs are available in powder or granulate form. They are usually dissolved in water to be swallowed. These include some painkillers and antibiotics for children (dry syrup).


In drops either the liquid itself is the active ingredient of the medicine, or the active ingredient has been dissolved in liquid, usually in water or a mixture of water and alcohol. Dosages are given in numbers of drops.

Liquid medications and syrups

In liquid medications, one or more active ingredients are usually dissolved or suspended in water. The liquid itself may also be the active ingredient. Nowadays these medications usually come with a measuring cup to help you get the dose right. People who have problems swallowing tablets often use liquid medications instead. Concentrated sugar solutions that contain medication are called syrups.


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  • Kretz FJ, Reichenberger S. Medikamentöse Therapie. Arzneimittellehre für Gesundheitsberufe. Stuttgart: Thieme; 2007.
  • Lüllmann H, Mohr K, Hein L. Taschenatlas Pharmakologie. Stuttgart: Thieme; 2014.
  • Plötz H. Kleine Arzneimittellehre für Fachberufe im Gesundheitswesen. Heidelberg: Springer; 2013.
  • IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

    Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. We do not offer individual consultations.

    Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

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