Drug & supplement interaction

N-acetyl Cysteine (nac) + Cyclopentolate

Cyclopentolate brand name: Cyclogyl.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 13, 2026

The bottom line No known interaction

We found no known interaction between N-acetyl Cysteine (nac) and Cyclopentolate in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

N-acetyl Cysteine (nac) and Cyclopentolate

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Cyclopentolate and N-acetyl Cysteine (nac) in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

N-acetyl Cysteine (nac) safety at a glance

N-acetyl Cysteine... overall Use caution Generally well tolerated at typical doses, but talk to a healthcare provider before use.

Pregnancy Possibly Safe When used orally, intratracheally, intravenously, or by inhalation. N-acetyl cysteine crosses the placenta, but has not been associated with adverse effects to... Read the full pregnancy detail

Breastfeeding Use caution There is not enough reliable safety information, so caution is advised.

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Pharmacist analysis

N-acetyl cysteine (NAC) has a number of potential interactions with several types of drugs.

This includes:

Activated charcoal
Anticoagulant/antiplatelet drugs
Antihypertensive drugs
Chloroquine
Nitroglycerin

All of these interactions are explained in detail on our individual drug-herbal interactions pages.

While there are no known interactions between NAC and the drug in this interaction inquiry, it is important to note that there simply may have a lack of studies to better understand potential issues.

Always let your doctor know about all the drugs and supplements you are taking.

— Dr. Brian Staiger, PharmD, BCPS

Still wondering about combining Cyclopentolate and N-acetyl Cysteine (nac)? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

How we checked

Why No Interaction Is Listed for Cyclopentolate

Interactions in our licensed database are recorded against drug classes, not just single drug names. Cyclopentolate is filed under a single classification — oral drugs. N-acetyl Cysteine (nac) has documented interactions with 5 drug classes — the most serious being nitroglycerin (major), activated charcoal (moderate) and anticoagulant/antiplatelet drugs (moderate) — and none of Cyclopentolate’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

N-acetyl Cysteine (nac) Does Interact With Other Medications

N-acetyl Cysteine (nac) has 1 major, 293 moderate known drug interactions in our database — Cyclopentolate isn’t one of them. If you take anything else, check it against the full list below.

Major 1 Moderate 293 No known interaction 2,536 (incl. Cyclopentolate)

Taking anything else?

Check Another of Your Medications Against N-acetyl Cysteine (nac)

Covers the 2,830 medications we’ve checked against N-acetyl Cysteine (nac). Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests N-acetyl Cysteine (nac) and Cyclopentolate May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. 2 of them are worth acting on rather than waiting out — marked below.

Confusion / Seizures Worth acting on Additional detail
N-acetyl Cysteine (nac)
“Orally, headache has been frequently reported with N-acetyl cysteine in clinical research. Other less common adverse effects reported in patients taking oral N-acetyl cysteine at a total daily dose of 600-1200 mg include dizziness, tiredness, vivid dreams, disorientation, and inability to concentrate.”

N-acetyl Cysteine (nac) · Natural Medicines adverse-effect record, reported in amyotrophic lateral sclerosis (als, lou gehrig's disease).
6 sources cited

7873. Estensen RD, Levy M, Klopp SJ, et al. N-acetylcysteine suppression of the proliferative index in the colon of patients with previous adenomatous colonic polyps. Cancer Lett 1999;147:109-14. PubMed

11430. Oldemeyer JB, Biddle WP, Wurdeman RL, et al. Acetylcysteine in the prevention of contrast-induced nephropathy after coronary angiography. Am Heart J 2003;146:E23. . PubMed

64510. Tirouvanziam, R., Conrad, C. K., Bottiglieri, T., Herzenberg, L. A., Moss, R. B., and Herzenberg, L. A. High-dose oral N-acetylcysteine, a glutathione prodrug, modulates inflammation in cystic fibrosis. Proc Natl.Acad.Sci U.S.A 3-21-2006;103(12):4628-463

64608. Berk, M., Copolov, D. L., Dean, O., Lu, K., Jeavons, S., Schapkaitz, I., Anderson-Hunt, M., and Bush, A. I. N-acetyl cysteine for depressive symptoms in bipolar disorder--a double-blind randomized placebo-controlled trial. Biol Psychiatry 9-15-2008;64(6) PubMed

64672. Rasmussen, J. B. and Glennow, C. Reduction in days of illness after long-term treatment with N-acetylcysteine controlled-release tablets in patients with chronic bronchitis. Eur.Respir.J 1988;1(4):351-355. DOI

64713. Miller, L. F. and Rumack, B. H. Clinical safety of high oral doses of acetylcysteine. Semin.Oncol 1983;10(1 Suppl 1):76-85.
Cyclopentolate

Listed in the ADVERSE REACTIONS section of the FDA label for Cyclopentolate. Read the label on DailyMed ›
A fast or pounding heartbeat Additional detail
N-acetyl Cysteine (nac)
“Intravenously, N-acetyl cysteine has been reported to significantly increase systolic and diastolic blood pressure after exposure to nitroglycerin when compared with placebo. Tachycardia, chest pain, angina, and transient sinus bradycardia have been rarely reported after administration of intravenous N-acetyl cysteine.

Intratracheally, infants receiving 5% N-acetyl cysteine every four hours for chronic lung disease h…”

N-acetyl Cysteine (nac) · Natural Medicines adverse-effect record, reported in angina.
6 sources cited

2280. Iversen HK. N-acetylcysteine enhances nitroglycerin-induced headache and cranial arterial responses. Clin Pharmacol Ther 1992;52:125-33. PubMed

7872. Arstall MA, Yang J, Stafford I, et al. N-acetylcysteine in combination with nitroglycerin and streptokinase for the treatment of evolving acute myocardial infarction. Safety and biochemical effects. Circulation 1995;92:2855-62.

64658. Dawson, A. H., Henry, D. A., and McEwen, J. Adverse reactions to N-acetylcysteine during treatment for paracetamol poisoning. Med J Aust. 3-20-1989;150(6):329-331.

64490. Bibi, H., Seifert, B., Oullette, M., and Belik, J. Intratracheal N-acetylcysteine use in infants with chronic lung disease. Acta Paediatr. 1992;81(4):335-339. PubMed

64675. Parr, G. D. and Huitson, A. Oral Fabrol (oral N-acetyl-cysteine) in chronic bronchitis. Br.J.Dis.Chest 1987;81(4):341-348.

64717. Jackson, I. M., Barnes, J., and Cooksey, P. Efficacy and tolerability of oral acetylcysteine (Fabrol) in chronic bronchitis: a double-blind placebo controlled study. J Int Med Res 1984;12(3):198-206. PubMed
Cyclopentolate

Listed in the ADVERSE REACTIONS section of the FDA label for Cyclopentolate. Read the label on DailyMed ›
A skin rash Additional detail
N-acetyl Cysteine (nac)
“Orally, N-acetyl cysteine may cause hives, flushing, and edema. Rash has also been reported. In one study, flushing was reported in 2% of patients receiving 600 mg of N-acetyl cysteine orally twice daily for six months.

Intravenously, N-acetyl cysteine may cause rash, and the occurrence seems to be more common than with oral use. Hives, facial edema, flushing, and pruritus have also been reported.”

N-acetyl Cysteine (nac) · Natural Medicines adverse-effect record, reported in erythema.
6 sources cited

64713. Miller, L. F. and Rumack, B. H. Clinical safety of high oral doses of acetylcysteine. Semin.Oncol 1983;10(1 Suppl 1):76-85.

64739. Long-term oral acetylcysteine in chronic bronchitis. a double-blind controlled study. Eur.J Respir.Dis.Suppl 1980;111:93-108.

64813. Charley, G., Dean, B. S., and Krenzelok, E. P. Oral N-acetylcysteine-induced urticaria: a case report. Vet.Hum Toxicol. 1987;29:477.

2260. De Flora S, Grassi C, Carati L. Attenuation of influenza-like symptomatology and improvement of cell-mediated immunity with long-term N-acetylcysteine treatment. Eur Respir J 1997;10:1535-41. PubMed

64715. Tattersall, A. B., Bridgman, K. M., and Huitson, A. Irish general practice study of acetylcysteine (Fabrol) in chronic bronchitis. J Int Med Res 1984;12(2):96-101. PubMed

64714. Boman, G., Backer, U., Larsson, S., Melander, B., and Wahlander, L. Oral acetylcysteine reduces exacerbation rate in chronic bronchitis: report of a trial organized by the Swedish Society for Pulmonary Diseases. Eur J Respir.Dis 1983;64(6):405-415.
Cyclopentolate

Listed in the ADVERSE REACTIONS section of the FDA label for Cyclopentolate. Read the label on DailyMed ›

Reported for N-acetyl Cysteine (nac) but not commonly for Cyclopentolate: a heart attack, stomach upset, a slow heartbeat and sore throat.

Effects for Cyclopentolate come from the ADVERSE REACTIONS section of its FDA label; effects for N-acetyl Cysteine (nac) come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

N-acetyl Cysteine (nac) in Pregnancy & Breastfeeding

Pregnancy Possibly Safe

When used orally, intratracheally, intravenously, or by inhalation. N-acetyl cysteine crosses the placenta, but has not been associated with adverse effects to the fetus. However, N-acetyl cysteine should only be used in pregnancy when clearly indicated, such as in cases of acetaminophen toxicity.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

Everything else you take

See Every Supplement That Interacts With Cyclopentolate

This page covers N-acetyl Cysteine (nac) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Cyclopentolate page lists 17 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 7 moderate · 9 minor.

From our pharmacist’s overview on the Cyclopentolate page

“Cyclopentolate (Cyclogyl) is the dilating drop used for eye exams, and even though it goes in the eye rather than your mouth, its interaction list still calls for real vigilance, starting with the single major-rated entry. That entry is activated charcoal, which can bind drugs and lower their levels in the body even when the drug was n…”

Reviewed by 2 · Jul 18, 2026

Open the Cyclopentolate interaction page

One more smart check

Taking N-acetyl Cysteine (nac) as Part of a Dietary Supplement Product? Check It for Interactions

We hold 3,554 real supplement products containing N-acetyl Cysteine (nac), each one broken down to its full ingredient list — and combination products often carry several ingredients besides N-acetyl Cysteine (nac). Even though N-acetyl Cysteine (nac) itself has no known interaction with Cyclopentolate, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where N-acetyl Cysteine (nac) and Cyclopentolate Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement N-acetyl Cysteine (nac)

Top 5%

#64 of 1,452 supplements looked up here in the last 7 days

29 days ago today

Medication Cyclopentolate

Top 5%

#113 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?

Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every N-acetyl Cysteine (nac) reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The N-acetyl Cysteine (nac) and Cyclopentolate records this page draws on were last updated July 11, 2026.
What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.

Data structure & sourcing designed and verified by Dr. Brian Staiger, PharmD, BCPS.

Supplement

About N-acetyl Cysteine (nac)

What is N-acetyl Cysteine (nac)?

Thinning mucus in lung conditions
Acetaminophen (Tylenol) overdose treatment
Antioxidant and glutathione support
Liver support
Respiratory health

N-acetyl cysteine (NAC) is a supplement form of the amino acid cysteine and a building block for the antioxidant glutathione. It has well-established prescription uses for acetaminophen overdose and thinning mucus, but evidence for many over-the-counter uses is still limited. It is generally well tolerated, but you should check with a pharmacist or doctor before starting it.

Not applicable (a modified form of the amino acid cysteine) · Capsules, tablets, powder, effervescent tablets, and prescription inhalation or injectable solutions

An interaction check asks whether these two react with each other — it does not ask whether N-acetyl Cysteine (nac) is a good idea for someone in your situation. Here is what our N-acetyl Cysteine (nac) record says about it on its own.

N-acetyl Cysteine (nac): dosing

There is no single standardized dose of NAC for general supplement use, and the right amount depends on why it is being used. Prescription uses, such as treating acetaminophen overdose, follow strict medical protocols and are handled only in a healthcare setting.For over-the-counter supplements, follow the directions on the product label and do not exceed the recommended amount.

From our N-acetyl Cysteine (nac) monograph — the full record covers uses, side effects and every documented interaction.

Read the full N-acetyl Cysteine (nac) monograph & all interactions

Medication

About Cyclopentolate Ophthalmic

What Is Cyclopentolate Ophthalmic Used For?

Brand name: Cyclogyl

Cyclopentolate hydrochloride ophthalmic solution is used to produce mydriasis (pupil dilation) and cycloplegia (temporary paralysis of the eye's focusing muscle). These effects allow eye care providers to examine the inside of the eye more thoroughly.

See full Cyclopentolate Ophthalmic drug information

Keep checking

Other Drugs & N-acetyl Cysteine (nac)

Browse every other medication we’ve checked against N-acetyl Cysteine (nac) — both the ones with a known interaction and the ones without. Select any drug for the full detail.

1Major

293Moderate

0Minor

2,535No known interaction

1 Major 293 Moderate 2,535 No interaction

Major

1 interaction

Nitroglycerin ›

Moderate

293 interactions

Showing 60 of 293 moderate interactions — see all 293 on the N-acetyl Cysteine (nac) page.

No interaction 2,535 drugs checked — show the list

We also checked N-acetyl Cysteine (nac) against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,535 medications checked with no known interaction — see the full N-acetyl Cysteine (nac) list.

See the full N-acetyl Cysteine (nac) interactions page

See every supplement checked against Cyclopentolate, ranked by severity

Evidence & sources

N-acetyl Cysteine (nac) References

The 86 references that drive our N-acetyl Cysteine (nac) monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
Jepsen S, Hansen AB. The influence of N-acetylcysteine on the measurement of prothrombin time and activated partial thromboplastin time in healthy subjects. Scand J Clin Lab Invest 1994;54:543-7. PubMed
van Zandwijk N, Dalesio O, Pastorino U, et al. EUROSCAN, a randomized trial of vitamin A and N-acetylcysteine in patients with head and neck cancer or lung cancer. For the European Organization for Research and Treatment of Cancer Head and Neck and Lung C DOI
Horowitz RS, Dart RC, Jarvie DR, et al. Placental transfer of N-acetylcysteine following human maternal acetaminophen toxicity. J Toxicol Clin Toxicol 1997;35:447-51.
Bailey B, McGuigan MA. Management of anaphylactoid reactions to intravenous N-acetylcysteine. Ann Emerg Med 1998;31:710-5. PubMed
Spiller HA, Krenzelok EP, Grande GA, et al. A prospective evaluation of the effect of activated charcoal before oral N-acetylcysteine in acetaminophen overdose. Ann Emerg Med 1994;23:519-23. PubMed
Ardissino D, Merlini PA, Savonitto S, et al. Effect of transdermal nitroglycerin or N-acetylcysteine, or both, in the long-term treatment of unstable angina pectoris. J Am Coll Cardiol 1997;29:941-7. PubMed
Horowitz JD, Henry CA, Syrjanen ML, et al. Nitroglycerine/N-acetylcysteine in the management of unstable angina pectoris. Eur Heart J 1988;9:95-100. PubMed
Louwerse ES, Weverling GJ, Bossuyt PM, et al. Randomized, double-blind, controlled trial of acetylcysteine in amyotrophic lateral sclerosis. Arch Neurol 1995;52:559-64. PubMed
Wiklund O, Fager G, Andersson A, et al. N-acetylcysteine treatment lowers plasma homocysteine but not serum lipoprotein(a) levels. Atherosclerosis 1996;119:99-106. PubMed
De Flora S, Grassi C, Carati L. Attenuation of influenza-like symptomatology and improvement of cell-mediated immunity with long-term N-acetylcysteine treatment. Eur Respir J 1997;10:1535-41. PubMed
Iversen HK. N-acetylcysteine enhances nitroglycerin-induced headache and cranial arterial responses. Clin Pharmacol Ther 1992;52:125-33. PubMed
Behr J, Maier K, Degenkolb B, et al. Antioxidative and clinical effects of high-dose N-acetylcysteine in fibrosing alveolitis. Adjunctive therapy to maintenance immunosuppression. Am J Respir Crit Care Med 1997;156:1897-901.
Tenenbein PK, Sitar DS, Tenenbein M. Interaction between N-acetylcysteine and activated charcoal: implications for the treatment of acetaminophen poisoning. Pharmacotherapy 2001;21:1331-6.
Arstall MA, Yang J, Stafford I, et al. N-acetylcysteine in combination with nitroglycerin and streptokinase for the treatment of evolving acute myocardial infarction. Safety and biochemical effects. Circulation 1995;92:2855-62.
Estensen RD, Levy M, Klopp SJ, et al. N-acetylcysteine suppression of the proliferative index in the colon of patients with previous adenomatous colonic polyps. Cancer Lett 1999;147:109-14. PubMed
Pela R, Calcagni AM, Subiaco S, et al. N-acetylcysteine reduces the exacerbation rate in patients with moderate to severe COPD. Respiration 1999;66:495-500.. PubMed
Oldemeyer JB, Biddle WP, Wurdeman RL, et al. Acetylcysteine in the prevention of contrast-induced nephropathy after coronary angiography. Am Heart J 2003;146:E23. . PubMed
Ekins BR, Ford DC, Thompson MI, et al. The effect of activated charcoal on N-acetylcysteine absorption in normal subjects. Am J Emerg Med. 1987;5(6):483-7. PubMed
Chamberlain JM, Gorman RL, Oderda GM, Klein-Schwartz W, Klein BL. Use of activated charcoal in a simulated poisoning with acetaminophen: a new loading dose for N-acetylcysteine? Ann Emerg Med. 1993;22(9):1398-402. PubMed
Renzi FP, Donovan JW, Martin TG, Morgan L, Harrison EF. Concomitant use of activated charcoal and N-acetylcysteine. Ann Emerg Med. 1985;14(6):568-72. DOI
North DS, Peterson RG, Krenzelok EP. Effect of activated charcoal administration on acetylcysteine serum levels in humans. Am J Hosp Pharm. 1981;38(7):1022-4. DOI
Loscalzo J. N-Acetylcysteine potentiates inhibition of platelet aggregation by nitroglycerin. J Clin Invest. 1985;76(2):703-8. PubMed
Ruiz FJ, Salom MG, Inglés AC, et al. N-acetyl-L-cysteine potentiates depressor response to captopril and enalaprilat in SHRs. Am J Physiol. 1994;267(3 Pt 2):R767-72. PubMed
Deharo E, Barkan D, Krugliak M, Golenser J, Ginsburg H. Potentiation of the antimalarial action of chloroquine in rodent malaria by drugs known to reduce cellular glutathione levels. Biochem Pharmacol. 2003;66(5):809-17. PubMed
Buckley, N. A., Whyte, I. M., O'Connell, D. L., and Dawson, A. H. Oral or intravenous N-acetylcysteine: which is the treatment of choice for acetaminophen (paracetamol) poisoning? J Toxicol.Clin Toxicol. 1999;37(6):759-767.
Sunman, W., Hughes, A. D., and Sever, P. S. Anaphylactoid response to intravenous acetylcysteine. Lancet 5-16-1992;339(8803):1231-1232. PubMed
Reynard, K., Riley, A., and Walker, B. E. Respiratory arrest after N-acetylcysteine for paracetamol overdose. Lancet 9-12-1992;340(8820):675. PubMed
BERNSTEIN, I. L. and AUSDENMOORE, R. W. IATROGENIC BRONCHOSPASM OCCURRING DURING CLINICAL TRIALS OF A NEW MUCOLYTIC AGENT, ACETYLCYSTEINE. Dis.Chest 1964;46:469-473. PubMed
REAS, H. W. THE USE OF N-ACETYLCYSTEINE IN THE TREATMENT OF CYSTIC FIBROSIS. J Pediatr 1964;65:542-557. PubMed
Bibi, H., Seifert, B., Oullette, M., and Belik, J. Intratracheal N-acetylcysteine use in infants with chronic lung disease. Acta Paediatr. 1992;81(4):335-339. PubMed
Jepsen, S., Herlevsen, P., Knudsen, P., Bud, M. I., and Klausen, N. O. Antioxidant treatment with N-acetylcysteine during adult respiratory distress syndrome: a prospective, randomized, placebo-controlled study. Crit Care Med 1992;20(7):918-923. PubMed
Roes, E. M., Raijmakers, M. T., Boo, T. M., Zusterzeel, P. L., Merkus, H. M., Peters, W. H., and Steegers, E. A. Oral N-acetylcysteine administration does not stabilise the process of established severe preeclampsia. Eur.J Obstet.Gynecol.Reprod.Biol 2006
Spiller, H. A., Winter, M. L., Klein-Schwartz, W., and Bangh, S. A. Efficacy of activated charcoal administered more than four hours after acetaminophen overdose. J Emerg.Med 2006;30(1):1-5. PubMed
Tirouvanziam, R., Conrad, C. K., Bottiglieri, T., Herzenberg, L. A., Moss, R. B., and Herzenberg, L. A. High-dose oral N-acetylcysteine, a glutathione prodrug, modulates inflammation in cystic fibrosis. Proc Natl.Acad.Sci U.S.A 3-21-2006;103(12):4628-463
Niemi, T. T., Munsterhjelm, E., Poyhia, R., Hynninen, M. S., and Salmenpera, M. T. The effect of N-acetylcysteine on blood coagulation and platelet function in patients undergoing open repair of abdominal aortic aneurysm. Blood Coagul.Fibrinolysis 2006;1 PubMed
Komisarof, J. A., Gilkey, G. M., Peters, D. M., Koudelka, C. W., Meyer, M. M., and Smith, S. M. N-acetylcysteine for patients with prolonged hypotension as prophylaxis for acute renal failure (NEPHRON). Crit Care Med 2007;35(2):435-441. PubMed
Grimble, G. K. Adverse gastrointestinal effects of arginine and related amino acids. J Nutr 2007;137(6 Suppl 2):1693S-1701S. PubMed
Berk, M., Copolov, D. L., Dean, O., Lu, K., Jeavons, S., Schapkaitz, I., Anderson-Hunt, M., and Bush, A. I. N-acetyl cysteine for depressive symptoms in bipolar disorder--a double-blind randomized placebo-controlled trial. Biol Psychiatry 9-15-2008;64(6) PubMed
Shahin, A. Y., Hassanin, I. M., Ismail, A. M., Kruessel, J. S., and Hirchenhain, J. Effect of oral N-acetyl cysteine on recurrent preterm labor following treatment for bacterial vaginosis. Int J Gynaecol.Obstet. 2009;104(1):44-48. PubMed
Nigwekar, S. U. and Kandula, P. N-acetylcysteine in cardiovascular-surgery-associated renal failure: a meta-analysis. Ann Thorac.Surg 2009;87(1):139-147. PubMed
Sandilands, E. A. and Bateman, D. N. Adverse reactions associated with acetylcysteine. Clin Toxicol.(Phila) 2009;47(2):81-88. PubMed
Wijeysundera, D. N., Karkouti, K., Rao, V., Granton, J. T., Chan, C. T., Raban, R., Carroll, J., Poonawala, H., and Beattie, W. S. N-acetylcysteine is associated with increased blood loss and blood product utilization during cardiac surgery. Crit Care Me PubMed
Holdiness, M. R. Clinical pharmacokinetics of N-acetylcysteine. Clin Pharmacokinet. 1991;20(2):123-134. PubMed
Dawson, A. H., Henry, D. A., and McEwen, J. Adverse reactions to N-acetylcysteine during treatment for paracetamol poisoning. Med J Aust. 3-20-1989;150(6):329-331.
Rasmussen, J. B. and Glennow, C. Reduction in days of illness after long-term treatment with N-acetylcysteine controlled-release tablets in patients with chronic bronchitis. Eur.Respir.J 1988;1(4):351-355. DOI
Walters, M. T., Rubin, C. E., Keightley, S. J., Ward, C. D., and Cawley, M. I. A double-blind, cross-over, study of oral N-acetylcysteine in Sjogren's syndrome. Scand J Rheumatol.Suppl 1986;61:253-258.
Cato, A., Goldstein, I., and Millman, M. A double-blind parallel study of acetylcysteine-isoproterenol and saline-isoproterenol in patients with chronic obstructive lung disease. J Int Med Res 1977;5(3):175-183. PubMed
Parr, G. D. and Huitson, A. Oral Fabrol (oral N-acetyl-cysteine) in chronic bronchitis. Br.J.Dis.Chest 1987;81(4):341-348.
Dano, G. Bronchospasm caused by acetylcysteine in children with bronchial asthma. Acta Allergol. 1971;26(3):181-190. DOI
Howatt, W. F. and DeMuth, G. R. A double-blind study of the use of acetylcysteine in patients with cystic fibrosis. Univ Mich.Med Cent.J 1966;32(2):82-85.
Millman, M. and Grundon, W. Use of acetylcysteine in bronchial asthma and emphysema. J Asthma Res 1969;6(4):199-209. PubMed
Vale, J. A. and Wheeler, D. C. Anaphylactoid reaction to acetylcysteine. Lancet 10-30-1982;2(8305):988.
Mant, T. G., Tempowski, J. H., Volans, G. N., and Talbot, J. C. Adverse reactions to acetylcysteine and effects of overdose. Br Med J (Clin Res Ed) 7-28-1984;289(6439):217-219. PubMed
Myers, C., Bonow, R., Palmeri, S., Jenkins, J., Corden, B., Locker, G., Doroshow, J., and Epstein, S. A randomized controlled trial assessing the prevention of doxorubicin cardiomyopathy by N-acetylcysteine. Semin.Oncol 1983;10(1 Suppl 1):53-55.
Miller, L. F. and Rumack, B. H. Clinical safety of high oral doses of acetylcysteine. Semin.Oncol 1983;10(1 Suppl 1):76-85.
Boman, G., Backer, U., Larsson, S., Melander, B., and Wahlander, L. Oral acetylcysteine reduces exacerbation rate in chronic bronchitis: report of a trial organized by the Swedish Society for Pulmonary Diseases. Eur J Respir.Dis 1983;64(6):405-415.
Tattersall, A. B., Bridgman, K. M., and Huitson, A. Irish general practice study of acetylcysteine (Fabrol) in chronic bronchitis. J Int Med Res 1984;12(2):96-101. PubMed
Jackson, I. M., Barnes, J., and Cooksey, P. Efficacy and tolerability of oral acetylcysteine (Fabrol) in chronic bronchitis: a double-blind placebo controlled study. J Int Med Res 1984;12(3):198-206. PubMed
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Bateman, D. N., Woodhouse, K. W., and Rawlins, M. D. Adverse reactions to N-acetylcysteine. Hum Toxicol. 1984;3(5):393-398. PubMed
Gervais, S., Lussier-Labelle, F., and Beaudet, G. Anaphylactoid reaction to acetylcysteine. Clin Pharm 1984;3(6):586-587.
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Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking N-acetyl Cysteine (nac) and Cyclopentolate Together: Common Questions

Is it safe to take N-acetyl Cysteine (nac) with Cyclopentolate?

We do not list a known interaction between N-acetyl Cysteine (nac) and Cyclopentolate. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.

Do N-acetyl Cysteine (nac) and Cyclopentolate have any of the same side effects?

Yes — our sources link each of them separately to 4 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.

How was the N-acetyl Cysteine (nac) and Cyclopentolate combination checked?

Interactions in our licensed database are recorded against drug classes. Cyclopentolate is filed under 1 classification, and N-acetyl Cysteine (nac) has documented interactions with 5 drug classes — none of Cyclopentolate's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.

Does N-acetyl Cysteine (nac) interact with any other medications?

Yes. N-acetyl Cysteine (nac) has 294 documented drug interactions in our database — Cyclopentolate is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

Does Cyclopentolate interact with any supplements?

Yes. Cyclopentolate has documented interactions with 17 supplements in our database — N-acetyl Cysteine (nac) is not one of them. The Cyclopentolate interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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N-acetyl Cysteine (nac) monograph Uses, safety profile, and every drug interaction in one place Cyclopentolate Ophthalmic drug information The full plain-English guide to this medication Cyclopentolate supplement interactions Every supplement checked against Cyclopentolate, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 86 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

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