THEOPHYLLINE ER 600 MG TABLET

What it is

THEOPHYLLINE ER 600 MG TABLET is how the CMS NADAC file names this product. The FDA NDC Directory lists it as “theophylline” and “theophylline anhydrous”, as its NDCs’ listings variously write the nonproprietary name, under the trade name “Theophylline (Anhydrous)”.

FDA gives its dosage form as tablet, extended release and its route as oral.

Its labelers, the companies named on the label, are Glenmark Pharmaceuticals Inc., USA and Westminster Pharmaceuticals, LLC.

FDA’s Established Pharmacologic Class for it is Methylxanthine.

The NADAC file of 2026-10-14 prices it under 2 NDCs (National Drug Codes).

NADAC classes it as a generic drug (rate-setting class G), and does not mark it as sold over the counter.

What pharmacies pay

Pharmacies pay $41.85 for 30 tablets (30 × $1.39516 per EA, rounded to the cent), by the CMS NADAC file of 2026-10-14; those prices took effect between 2025-11-19 and 2026-01-14. That is what pharmacies pay their suppliers, not what they charge you.

NADAC’s explanation code for it: 4, carried forward from the previous file.

The NADAC of all 2 NDCs was carried forward from an earlier file (NADAC explanation code 2 or 4), not newly surveyed: those prices took effect on 2025-11-19, 2026-01-14. The file is new; the price is not.

What NADAC measures · Why 30 tablets · NADAC explanation codes · Carried-forward prices

All 2 NDCs

• 68462-0356-01 · Glenmark Pharmaceuticals Inc., USA · $1.39516 per EA · eff. 2025-11-19 filed carried forward
• 69367-0415-01 · Westminster Pharmaceuticals, LLC · $1.39516 per EA · eff. 2026-01-14 filed carried forward

Other strengths, forms and brands

8 other products in the NADAC file share an FDA nonproprietary name with THEOPHYLLINE ER 600 MG TABLET.

Part D is one average per brand and generic name, over every strength and form.

CMS NADAC · nadac-national-average-drug-acquisition-cost-20261014.csv · eff. between 2025-11-19 and 2026-09-23 (5 dates) · as of 2026-10-14 · retrieved 2026-10-17

Medicare Part D · DSD_PTD_RY26_P04_V10_DY24_BGM.csv · eff. 2024-01-01 to 2024-12-31 · as of 2026-06-25 · retrieved 2026-10-18

Compared with its class

The middle of its 2 NDCs’ NADAC prices is $1.39516 per EA filed.

Of the 32 other products in FDA’s Methylxanthine class priced per EA, 7 have a higher middle NADAC price and 25 a lower one. The one in the middle is QC STAY AWAKE 200 MG TABLET, at $0.08299 per EA filed (eff. 2026-09-23).

Prices are compared per unit, whatever the strength or dose, and a class is not a list of substitutes.

CMS NADAC · nadac-national-average-drug-acquisition-cost-20261014.csv · eff. 2025-11-19, 2026-09-23 · as of 2026-10-14 · retrieved 2026-10-17

How the class comparison works

What Medicare paid

Medicare Part D paid $38.79 for 30 tablets, at an average of $1.29285 per EA in 2024 (2024-01-01 to 2024-12-31) for “Theophylline ER” and “Theophylline Anhydrous”, every strength and form sold under that name together (Medicare Part D Spending by Drug, file of 2026-06-25).

That average covers 163,518 Part D claims (fills, including refills) for 2024-01-01 to 2024-12-31, across every maker, strength and form under the name.

Medicare's price is not your price.

What Part D spending measures · Which Medicare figure OpenBill compares · How the spread is worked out

What to ask at the counter

None of these figures is your price: what you pay depends on your pharmacy, your insurance, coupons and discounts.

• What is your cash price for 30 tablets? Is it lower than what I would pay through my insurance?
• If you have Medicare Part D: what is my plan’s copay or coinsurance for it? The Part D average on this page is not what you pay.
• These are questions about price, not medical advice. Do not change or stop a medicine without talking to your prescriber or pharmacist.