DEPAKOTE ER vs LAMOTRIGINE

Independent side-by-side comparison.

Rated against independent regulatory sources·Last updated August 19, 2026·How we rate

Possible drug interaction. DEPAKOTE ER and LAMOTRIGINE are different prescription medicines. Combining or switching between them can cause interactions — talk to a pharmacist or prescriber before making changes. This page is not medical advice.

Attribute	DEPAKOTE ER	LAMOTRIGINE
Rating	70/100	New
Pharmacy pays	~$5.99 /30	~$4.39 /30
Type	RX	RX
Active ingredient	DIVALPROEX SODIUM	LAMOTRIGINE
Manufacturer	Abbott	Rubicon Research
Dosage forms	Tablet, extended release	Tablet, Tablet, chewable, Tablet, extended release, Tablet, orally disintegrating, Kit
Drug class	Anti-Epileptic Agent	Anti-Epileptic Agent
Boxed warning	None	None
Half-life	about 9 to 16 hours (the label's mean terminal half-life range for valproate monotherapy)	about 25 to 33 hours in healthy adults taking no other medications — the label reports a mean elimination half-life of 32.8 hours after a single dose (individual range 14 to 103 hours) and 25.4 hours with repeat dosing (range 11.6 to 61.6 hours), since lamotrigine induces its own metabolism
Treats	Bipolar Disorder, Epilepsy, Absence Epilepsy	Bipolar Disorder, Partial Epilepsies, Seizures

depakote er lamotrigine

Rating

70/100

New

Pharmacy pays

~$5.99 /30

~$4.39 /30

Type

Active ingredient

DIVALPROEX SODIUM

LAMOTRIGINE

Manufacturer

Abbott

Rubicon Research

Dosage forms

Tablet, extended release

Tablet, Tablet, chewable, Tablet, extended release, Tablet, orally disintegrating, Kit

Drug class

Anti-Epileptic Agent

Boxed warning

None

Half-life

about 9 to 16 hours (the label's mean terminal half-life range for valproate monotherapy)

about 25 to 33 hours in healthy adults taking no other medications — the label reports a mean elimination half-life of 32.8 hours after a single dose (individual range 14 to 103 hours) and 25.4 hours with repeat dosing (range 11.6 to 61.6 hours), since lamotrigine induces its own metabolism

Treats

Bipolar Disorder, Epilepsy, Absence Epilepsy

Bipolar Disorder, Partial Epilepsies, Seizures

Frequently asked questions

Which is cheaper, Depakote ER or Lamotrigine?

Lamotrigine costs pharmacies less to acquire — about $4.39 vs $5.99 for a 30-count supply, per the CMS NADAC survey. That gap is in the pharmacy's cost of goods, not necessarily in what you pay: your price is set afterwards by your insurer and the pharmacy.

What is the difference between Depakote ER and Lamotrigine?

Depakote ER contains Divalproex Sodium, while Lamotrigine contains Lamotrigine — they have different active ingredients.

Ratings are based on FDA regulatory (recall-safety) data. This comparison is for general reference only — not medical advice. Always consult a licensed professional before choosing or switching a medication.