Where can I find medication absorbiton charts?per rectum, ingestion(oral),intravenous (iv),intraosseous(io),subcutaneous(sc),inhalation,sublingual,transcutaneous
I am sorry to report that you will likely be unable to find an absorption chart for all drugs in general. This is because the absorption rate of drugs is affected by many, many variables, among which some are listed as follows:
1. The form of the drug (tablet, capsule, sustained release, etc.)
2. The pharmacokinetics of each particular drug, no two drugs having identical features. Pharmacokinetics deals with the chemical composition of the drug (such as acidity or alkalinity), method of absorption into the body, effect of other drugs and food, distribution of the particular drug to organs in the body once it has been absorbed, bioavailability of the drug to the tissues once absorbed, metabolism of the drug within the body, half-life and excretion of the drug.
3. The route of administration of the drug (oral, rectal, intravenous, intramuscular, etc.)
4. And many others.
Peak and Trough drug levels:
One can get an idea of absorption time for drugs by measuring blood levels of the drug at various times following ingestion or injection. One should study the peak level (maximal level attained for a given dose), the trough level (lowest level measured between doses, usually just before the next scheduled dose) and therapeutic level (the level which has been determined to provide the best intended medical effect). By knowing the times for peak and trough levels you can get a good idea about time of absorption.
Absorption tables are available for specific drugs or small classes or groups of drugs, but I have not found tables that list hundreds of different drugs.
The web links given here amplify these concepts.
The first gives peak and trough times, therapeutic and toxic levels and half-lives for a large number of drugs. It may be the closest thing to the type of table you seek.
The next provides basic information on drug metabolism, bioavailability, distribution in tissue and excretion. It will clarify why the table you seek is unlikely to be found.
The last is a veterinary article that just happens to give an excellent basic general discussion of important concepts such as drug absorption, clearance, volume of distribution and half-life.