Lamotrigine and Blood Pressure: Effects and Considerations
Lamotrigine does not typically cause hypertension or elevate blood pressure, and there is no substantial evidence in current guidelines linking lamotrigine to hypertension as a common or significant adverse effect.
Cardiovascular Effects of Lamotrigine
Lamotrigine is an anticonvulsant medication commonly used to treat epilepsy and bipolar disorder. When examining its cardiovascular profile:
The FDA recently (2020) added a warning to lamotrigine's label regarding potential cardiac rhythm and conduction abnormalities based on in vitro data suggesting Class IB antiarrhythmic effects 1.
However, a retrospective study in a veteran population (a particularly vulnerable group) found no unambiguous cardiac complications related to lamotrigine, with less than 10% showing any potential EKG abnormalities even using permissive criteria 1.
Notably, hypertension is not listed among the common or significant adverse effects of lamotrigine in clinical guidelines or drug information resources 2.
Potential Cardiovascular Considerations
While lamotrigine does not typically cause hypertension, there are some cardiovascular considerations:
In cases of acute lamotrigine overdose, cardiovascular toxicities including hypotension (12%), wide complex tachycardia and cardiac arrest (6%) have been reported, but these occur primarily in adult patients with serum concentrations >25 mg/L 3.
A study examining cerebral blood flow found that lamotrigine reduced perfusion in cortico-thalamo-limbic areas, orbitofrontal cortex, and brainstem in patients with idiopathic generalized epilepsy 4, but this was not associated with systemic blood pressure changes.
Medication Management Considerations
When prescribing lamotrigine, healthcare providers should:
Monitor for the more common adverse effects of lamotrigine, which include skin rash (which can be serious), headache, nausea, dizziness, somnolence, and ataxia 2.
Be aware that psychiatric symptoms have been reported with lamotrigine use, including affective switches, psychotic episodes, and hallucinations 5.
Consider potential drug interactions, particularly with other medications that might affect blood pressure. For example, lamotrigine can decrease the effectiveness of some medications like lamotrigine 2.
Blood Pressure Monitoring
For patients taking lamotrigine:
Routine blood pressure monitoring is appropriate as part of standard care, but there is no specific recommendation for more intensive monitoring based solely on lamotrigine use.
According to current hypertension guidelines, blood pressure should be monitored every 3 months until target is reached, with follow-up within 1-2 weeks after medication initiation 6.
Conclusion
Based on the available evidence, lamotrigine is not associated with hypertension or blood pressure elevation as a common adverse effect. The focus of monitoring should be on the known adverse effects of lamotrigine, including skin reactions, neurological effects, and the recently added warning about cardiac conduction abnormalities. If a patient on lamotrigine develops hypertension, clinicians should consider other causes rather than attributing it to lamotrigine therapy.