Following are the routes of drug administration.
1)Oral
2)Nasal Inhalation
3)Sublingual
4)Intravenous
5)Intramuscular
6)Subcutaneous
7)Topical (local effects)
8)Transdermal
9)Rectal
PHARAMCOKINETICS;
Pharmacokinetics describes what body does with drugs.
>There are four pharmacokinetics process;
1)Absorption
2)Distribution
3)Metabolism
4)Elimination
1)ABSORPTION;
>Entry of drugs into bloodstream.
a) RATE OF ABSORPTION;
*Rate of drugs Absorption depends upon;
1)Environment of The site where the drug is absorbed.
2)chemical characteristic of drug.
3)Route of administration
b) MECANISM OF ABSORPTION FROM GIT;
1)Passive Diffusion;
>Movement of drugs from high concentration to their low concentration.
>No carrier is required
>Majority of drugs are absorbed by this mechanism.
2)Facilitated Diffusion;
>Some drugs are absorbed by the help of carrier proteins. This process is called facilitated diffusion.
>No energy is required
3) Active Transport;
>Absorption of drugs by using energy(hydrolysis of ATP) from their low concentration to their high concentration is called active transport.
>Selective
4)ENDOCYTOSIS
>Engulfment of a drug by cell membrane is called endocytosis.
2) DISTRIBUTION;
>After the entry of drugs into bloodstream then the drugs are distributed into the interstitial and intracellular fluids.
METABOLISM;
After distribution of drugs they are metabolized by liver or other tissues.
ELIMINATION;
After metabolism drugs and the metabolites are released from the body with urine, bile or feces.