ARIMIDEX vs FEMARA

Independent side-by-side comparison.

Rated against independent regulatory sources·Last updated August 21, 2026·How we rate

Possible drug interaction. ARIMIDEX and FEMARA 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	ARIMIDEX	FEMARA
Rating	70/100	70/100
Pharmacy pays	~$4.15 /30	~$4.50 /30
Type	RX	RX
Active ingredient	ANASTROZOLE	LETROZOLE
Manufacturer	Astrazeneca	Novartis
Dosage forms	Tablet	Tablet
Drug class	Aromatase Inhibitor	Aromatase Inhibitor
Boxed warning	None	None
Half-life	—	about 2 days (terminal elimination half-life)
Treats	Breast Neoplasms	Breast Neoplasms

arimidex femara

Rating

70/100

Pharmacy pays

~$4.15 /30

~$4.50 /30

Type

Active ingredient

ANASTROZOLE

LETROZOLE

Manufacturer

Astrazeneca

Novartis

Dosage forms

Tablet

Drug class

Aromatase Inhibitor

Boxed warning

None

Half-life

—

about 2 days (terminal elimination half-life)

Treats

Breast Neoplasms

Frequently asked questions

Which is better-rated, Arimidex or Femara?

Arimidex and Femara are tied at 3.5 out of 5 by our independent rating.

Which is cheaper, Arimidex or Femara?

Arimidex costs pharmacies less to acquire — about $4.15 vs $4.50 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 Arimidex and Femara?

Arimidex contains Anastrozole, while Femara contains Letrozole — 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.