A capsule is a type of medication dosing form that is commonly used for the oral administration of drugs. It is a small, solid, and usually cylindrical or spherical container that is made of gelatin or other materials. Inside the capsule, there may be one or more active drug ingredients or a combination of these ingredients in either powder, liquid, or granular form.

Capsules come in different sizes, colors, and shapes. These variations are usually intended to differentiate between different medication dosages or active ingredient combinations. Capsules can also be modified to release their contents in different ways, including immediate release, delayed release, extended release or enteric-coated.

Capsules can provide several benefits over other types of medication dosing forms such as tablets, syrups, or injections. They can be more convenient to take, especially for individuals with swallowing difficulties, and they are often more stable than liquid medications, which can be easily spilled or degraded.

In summary, capsules are solid containers that can contain one or more active drug ingredients, come in different sizes, shapes, and colors, and can be modified to release their contents in different ways. Capsules are often preferred over other medication dosing forms due to their convenience and stability.