From the FDA Drug Label
The therapeutic range is commonly considered to be 50 to 100 μg/mL of total valproate, although some patients may be controlled with lower or higher plasma concentrations Therapeutic valproate serum concentrations for most patients with absence seizures is considered to range from 50 to 100 μg/mL. Some patients may be controlled with lower or higher serum concentrations
A valproic acid level of 31 mcg/mL is below the commonly considered therapeutic range of 50 to 100 μg/mL. Therefore, it is not considered therapeutic. 1 1
From the Research
A valproic acid level of 31 micrograms per milliliter (mcg/mL) is below the standard therapeutic range, which may result in suboptimal seizure control or inadequate management of other conditions like bipolar disorder. The generally accepted therapeutic range for valproic acid is between 50-100 mcg/mL for most indications, with some sources citing a wider range of 50-125 mcg/mL. At 31 mcg/mL, the level is below the standard therapeutic range, which may result in suboptimal seizure control or inadequate management of other conditions like bipolar disorder. Patients with levels below the therapeutic range may experience breakthrough symptoms. However, some individuals do respond well to lower levels, so clinical response should always be considered alongside laboratory values. If a patient is experiencing good symptom control at this level and not having side effects, the physician might choose to maintain this dose. If symptoms are not adequately controlled, a dosage adjustment may be necessary to achieve levels within the therapeutic range. Regular monitoring of valproic acid levels is important, especially after dosage changes, to ensure efficacy while avoiding toxicity, as suggested by 2. Some studies have highlighted the importance of considering individual factors, such as hypoalbuminemia, which can affect valproic acid levels, as seen in 3. Additionally, the use of valproic acid in certain populations, such as women of childbearing potential, requires careful consideration of the risks and benefits, as discussed in 4. Key points to consider include:
- The therapeutic range for valproic acid is between 50-100 mcg/mL for most indications.
- Levels below the therapeutic range may result in suboptimal seizure control or inadequate management of other conditions.
- Clinical response should be considered alongside laboratory values when determining the appropriateness of a valproic acid level.
- Regular monitoring of valproic acid levels is important to ensure efficacy and avoid toxicity.
- Individual factors, such as hypoalbuminemia, and population-specific considerations, such as use in women of childbearing potential, should be taken into account when using valproic acid, as noted in 5 and 6.