Absorption (pharmacokinetics)
Absorption (pharmacokinetics)
Absorption in pharmacokinetics refers to the process by which a drug or other substance moves from the site of administration to the bloodstream. This process is crucial in determining the onset, intensity, and duration of a drug's effect.
Mechanisms of Absorption[edit | edit source]
There are several mechanisms by which drugs are absorbed into the body. These include:
- Passive diffusion: This is the most common mechanism of drug absorption. It involves the movement of drug molecules from an area of high concentration (the site of administration) to an area of low concentration (the bloodstream).
- Facilitated diffusion: In this process, carrier proteins in the cell membrane assist in the movement of drug molecules across the membrane.
- Active transport: This mechanism involves the use of energy to move drug molecules against a concentration gradient.
- Endocytosis and exocytosis: These processes involve the engulfing of drug molecules by the cell membrane and their subsequent release into the cell or extracellular space, respectively.
Factors Affecting Absorption[edit | edit source]
Several factors can affect the rate and extent of drug absorption. These include:
- Drug formulation and dosage form: The physical and chemical properties of the drug and its formulation can significantly impact absorption.
- Route of administration: The path by which a drug is introduced into the body can influence its absorption. For example, drugs administered orally must survive passage through the gastrointestinal tract, which can affect their absorption.
- Physiological factors: Individual characteristics such as age, sex, body weight, and health status can also influence drug absorption.
Clinical Significance[edit | edit source]
Understanding the absorption process is critical in pharmacotherapy as it helps in determining the dosage regimen and the route of administration for a drug. It also plays a key role in predicting the drug's bioavailability, which is the proportion of the administered drug that reaches the systemic circulation.
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
WikiMD's Wellness Encyclopedia |
Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD