Drug Handling in the Body Flashcards
Drug disposition IADDME
Intake Absorption Distribution Drug-cell interaction Metabolism Excretion
Types of drug administration
Oral Topical (Skin) Transdermal (Under skin) Rectal Inhalation Parenteral
What are the parenteral routes of administration?
Intravenous Intramuscular Intradermal Intrathecal (into subarachnoid space) Subcutaneous Epidural
Drugs have to be ______ soluble to pass into the blood.
Lipid-soluble
Movement of drugs across membranes
1, passage through water channels
2, endocytosis
3, passive diffusion
4, facilitated or active transport
What is facilitated transport?
Drug moves down concentration gradient through protein channels. No energy is needed.
What is active transport?
Drug moves against concentration gradient using ATP
What is endocytosis?
A form of active transport in which a cell transports molecules (such as proteins) into the cell by engulfing them in an energy-using process.
Which organ gets the most blood flow?
Kidney
Which organ gets the 2nd most blood flow?
Myocardium/heart
Drugs can bind to proteins in the blood like…
Albumin
What is drug metabolism?
The enzyme-mediated conversion of a lipid-soluble compound into a more water-soluble one.
Where does the most metabolism take place?
The liver
Smooth endoplasmic reticulum.
What happens in phase 1 metabolism?
Chemical structure of drug is modified.
Drug made more water-soluble.
Drugs prepared for phase 2
Are the products of phase 1 metabolism more or less chemically reactive than the parent drug?
More
What happens in phase 2 reactions?
Conjugate drug to large molecules. Products are: -Water-soluble -Increased molecular weight -Inactive
How is drug excretion increased?
- Increase blood flow to the kidneys
- Decrease plasma protein binding
How can drugs be excreted?
- Urine
- Bile
- faeces
- lungs
- Skin
What is the half-life of a drug?
The time it takes for the amount of drug in the body to decrease to one-half of the peak level. The rate at which drugs are eliminated from the body.
What is the therapeutic window?
The window between the minimum therapeutic concentration and the minimum toxic concentration.
