Drug Interaction Report

Acetazolamide and Cyclosporine Injection: Interaction Details

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Acetazolamide

Diamox® Sequels®
+

Cyclosporine Injection

Atopica Cequa Cyclavance Gengraf Modulis Neoral Optimmune Restasis
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Updated Aug 8, 2026
LinkedIn
Interaction severity
Moderate
Can be significant — usually manageable with monitoring.
How we grade severity & evidence

Severity levels

  • Contraindicated: These should generally not be used together.
  • Major: Potentially serious — often needs a change or close monitoring.
  • Moderate: Can be significant — usually manageable with monitoring.
  • Minor: Usually limited clinical impact.

Evidence grades

  • Established: Well documented — supported by controlled studies or strong clinical data.
  • Probable: Good supporting evidence, though not definitively proven.
  • Suspected: Some evidence suggests this interaction, but it is not well established.
  • Possible: Limited or conflicting evidence; the interaction may occur.
  • Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.

Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.

Of 46 documented Acetazolamide interactions, 9 are rated moderate — including this one.
Onset
delayed
Evidence
probable
Severity
Moderate

What happens

An increased risk of cycloSPORINE toxicity

Interaction Deep Dive

Concomitant use of acetaZOLAMIDE with cycloSPORINE may elevate cycloSPORINE levels1. With the addition of acetaZOLAMIDE (1000 mg daily) in a patient stabilized on cycloSPORINE (concentration 290 ng/mL), the cycloSPORINE concentration significantly increased (1700 ng/mL) one month after starting acetaZOLAMIDE 2. In another report, three men receiving cycloSPORINE and acetaZOLAMIDE experienced an increase in their mean cycloSPORINE concentration from 170 ng/mL to 1130 ng/mL 3.

Why it happens (mechanism)

Decreased cycloSPORINE clearance

Literature reports

2 reports — tap to read

a) Concomitant administration of cycloSPORINE with acetaZOLAMIDE was reported to result in increases in cycloSPORINE serum levels and cycloSPORINE toxicity (renal impairment and neurotoxicity) in a 50-year-old cardiac transplant recipient 2. Symptoms of toxicity subsided following withdrawal of acetaZOLAMIDE and reduction of the dose of cycloSPORINE. More studies are required to evaluate the mechanism of this interaction.

b) CycloSPORINE trough blood levels were determined before and 72 hours after coadministration with acetaZOLAMIDE in three men. Mean trough cycloSPORINE levels prior to acetaZOLAMIDE therapy were 170 ng/mL (range 54 ng/mL to 270 ng/mL). Following acetaZOLAMIDE, mean trough cycloSPORINE levels increased to 1130 ng/mL (range 517 ng/mL to 1827 ng/mL) 3.

Common questions

Can I take Acetazolamide and Cyclosporine Injection together?

An increased risk of cycloSPORINE toxicity Always confirm with your pharmacist or prescriber before making any change.

How serious is the Acetazolamide and Cyclosporine Injection interaction?

It is rated moderate. Can be significant — usually manageable with monitoring.

How quickly could this interaction happen?

The documented onset is "delayed". Effects tend to build up gradually over days to weeks.

How strong is the evidence for this interaction?

The evidence is graded "probable". Good supporting evidence, though not definitively proven.

Questions for your pharmacist

  • Does my dose of Acetazolamide or Cyclosporine Injection need adjusting while I take them together?
  • What symptoms should prompt me to call you or my prescriber right away?
  • Does the timing of my doses matter for this combination?
  • Is there anything you'd monitor while I'm on both?

References (3)

  1. Product Information: Acetazolamide oral extended-release capsules, acetazolamide oral extended-release capsules. Micro Labs USA Inc (per DailyMed), Somerset, NJ, 2022. DailyMed
  2. Keogh A, Esmore D, Spratt P, et al: Acetazolamide and cyclosporine. Transplantation 1988; 46:478-479. PubMed
  3. Tabbara KF, Al-Faisal Z, & Al-Rashed W: Interaction between acetazolamide and cyclosporine. Arch Ophthalmol 1998; 116:832-833. DOI
Was this write-up helpful?
Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

Check another combination

Our instant two-drug interaction checker is almost here.

Coming soon

The instant two-drug checker is on its way.

In the meantime, browse the directory below to look up any drug and see its documented interactions.

Still have questions about this combination?

Every question gets a real answer from a licensed pharmacist — free, and usually within a day.

Ask the pharmacist
This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.