Therapeutic drug levels
Therapeutic Drug Levels
Therapeutic drug levels are measurements of the amount of a prescription drug that are found in a patient's bloodstream. This is important to measuring the effectiveness of a specific medication and to ensure it is not having any adverse effects on the patient. Different medications have different therapeutic drug levels that are considered to be effective.
Preparation
In order to measure a therapeutic drug level, a physician will usually order a blood test. This will be carried out in a laboratory setting and involves taking a blood sample from the patient and then analysing it. The results will then be sent back to the doctor so they can assess whether or not the medication is having the desired effect.
Procedure
The procedure to measure therapeutic drug levels is simple and straightforward. First, a phlebotomist will take a blood sample from the patient and label it with the patient’s name and the medications they are taking. The sample will then be sent to a laboratory where they will analyse it and measure the level of drugs in the patient’s bloodstream. Once the readings are taken, the results will be sent back to the doctor so they can assess whether or not the medication is having the desired effect.
Types of Therapeutic Drug Levels
- Peak Levels: Peak levels are the highest concentration of a medication in a patient's blood stream. Peak levels are typically taken two to four hours after taking medication.
- Trough Levels: Trough levels are the lowest concentration of a medication in a patient's blood stream. Trough levels are typically taken just before the patient takes the medication.
- Urinary Levels: Urinary levels measure the amount of medication that is eliminated in the urine. This can be an indication of how quickly the patient's body is processing and eliminating the medication.
Risks
The risks of measuring therapeutic drug levels are generally considered to be minimal. The only possible risk is a slight discomfort from having the blood taken for the test. Additionally, there is always the possibility of false positives or false negatives when the test results are sent back.
Why Measure Therapeutic Drug Levels
Measuring therapeutic drug levels is important to ensure that the patient is taking the correct amount of medication for their condition. This is especially important for antibiotics, and other medications that have the potential for causing serious side effects if taken in too high a dose. In addition, therapeutic drug levels play an important role in helping healthcare providers to adjust medications if they are proving ineffective.
When to Measure Therapeutic Drug Levels
Therapeutic drug levels should be measured in all patients that are taking prescription medications. The frequency of measurement will depend on the medication and the individual patient, but it is generally recommended that therapeutic drug levels should be measured at least once every six months. Additionally, in some cases, physicians may recommend more frequent monitoring to ensure the effectiveness of the medication.