Therapeutic Levels
In theory this is how "therapeutic levels" work.
A patient is started on an epilepsy medication and slowly the dosage is increased until one of two things happen.....seizure control or unacceptable side effects occur. There is a range of "magic" blood levels, a range of "numbers" for each medicine based on the amount of the medicine in the blood. This is called the "Therapeutic Range". Therapeutic Level is a number that falls within this range. Some people actually do achieve seizure control at levels higher than these numbers where others would be "toxic".
What is important to remember is that everyone reacts differently to the same medicine. The test to check Therapeutic Levels is a blood test. Pharmacokinetics is the study of the movement of drugs through the body. When medicine is taken it is dissolved in the stomach and absorbed by blood vessels in the intestines (some meds are absorbed also by the liver & kidneys). Once in the blood, your body then will try to get rid of the drug through metabolism by the liver and filtering by the kidneys. Biotransformation (metabolism) is a major mechanism for drug elimination. This metabolism ends the pharmacologic action of the drug & increases removal from the body. Most of this is done by the liver.The kidney is the major route of excretion for most drugs. The blood level will drop after reaching a Peak Level. The "Half Life" of a drug is the time it takes for the blood level of the drug to drop by one half. A person with a faster metabolism will have a shorter Half Life on the same drug as a person with a slower metabolism. This is only one difference in how we react to the same medicine differently....metabolism.
Since doctors like to use Therapeutic Levels it is important to take your medicine at the same time every day, have blood levels checked at the same time of the day and do not miss doses of your medicine.
A Blood Level is a tool, a guideline. What is important is seizure control, how you are feeling, side effects from the medicine and that you are not experiencing any Adverse Affects. Adverse Affects are the bad side effects that can be signs that you are toxic from your medicine, you are on too high of a dose or you have accidentally taken an overdose. Read the printouts from your pharmacist about the medicines you take, your pharmacist can answer your questions.
A good doctor will use the blood level only as a guideline and will listen to the patient. A good doctor TREATS the patient NOT a NUMBER.
Other tests that are necessary when taking epilepsy medicine. These tests should be done before starting the medicine so that tests are available to use as a baseline. See the links on the Main Page for information on these tests.
Liver Function Tests - for medicines absorbed by the liver
CBC - Complete Blood Count
written by Jeff Morgan 1999 this text is a general explanation of Blood Levels & Therapeuric Levels.......questions should be directed to your physician & pharmacist