Drug Interaction Report

Cyclopentolate Ophthalmic and Amantadine: Interaction Details

A pharmacist-reviewed analysis of the Cyclopentolate Ophthalmic and Amantadine interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

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

Amantadine

No brand names on record
+

Cyclopentolate Ophthalmic

Akpentolate® Cyclogyl Cyclogyl® Cyclomydril® (as a combination product containing Cyclopentolate, Phenylephrine) Cylate Pentolair®
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Major
Potentially serious — often needs a change or close 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 Cyclopentolate Ophthalmic interactions, 39 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
unspecified
Evidence
theoretical
Severity
Major

What happens

Potentiation of anticholinergic effects

Interaction Deep Dive

Concomitant use of amantadine with anticholinergic drugs may potentiate the anticholinergic-like side effects of amantadine21. Coadministration has been resulted in a potentiation of anticholinergic side effects, including confusion and hallucinations in patients receiving close to maximum tolerable doses of an anticholinergic (trihexyphenidyl, benztropine) 3. If they must be used concurrently, reduce the dose of the anticholinergic drug or amantadine if atropine-like side effects occur 2.

Why it happens (mechanism)

Additive anticholinergic properties

Literature reports

1 report — tap to read

a) Concomitant amantadine and anticholinergic drug therapy has been reported to result in a potentiation of anticholinergic side effects, including confusion and hallucinations in patients receiving close to maximum tolerable doses of an anticholinergic (trihexyphenidyl, benztropine) 3.

Common questions

Can I take Cyclopentolate Ophthalmic and Amantadine together?

Potentiation of anticholinergic effects Always confirm with your pharmacist or prescriber before making any change.

How serious is the Cyclopentolate Ophthalmic and Amantadine interaction?

It is rated major. Potentially serious — often needs a change or close monitoring.

How quickly could this interaction happen?

The documented onset is "unspecified". The timing of this interaction is not well characterized.

How strong is the evidence for this interaction?

The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.

Questions for your pharmacist

  • Does my dose of Cyclopentolate Ophthalmic or Amantadine 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 a safer alternative to one of these medications for me?

References (3)

  1. Product Information: PREVDUO intravenous injection, neostigmine methylsulfate glycopyrrolate intravenous injection. Slayback Pharma LLC (per FDA), Princeton, NJ, 2023. DailyMed
  2. Product Information: OSMOLEX ER(TM) oral extended-release tablets, amantadine oral extended-release tablets. Vertical Pharmaceuticals, LLC (per manufacturer), Bridgewater, NJ, 2018. DailyMed
  3. Postma JU & Tilburg WV: Visual hallucinations and delirium during treatment with amantadine (Symmetrel(R)). J Am Geriatr Soc 1975; 23:212-215. PubMed
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Amantadine

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All Amantadine interactions (22)
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Cyclopentolate Ophthalmic

Keep reading about Cyclopentolate Ophthalmic

All Cyclopentolate Ophthalmic interactions (46) Cyclopentolate Ophthalmic drug information
Also serious with: Potassium Citrate Potassium Chloride Alfentanil Amifampridine
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:

Amantadine + Activated Charcoal Henbane Scopolia Angel's Trumpet Bacopa Belladonna Betel Nut Boxwood + 38 more

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

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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.