Skip to content
My WebMD Sign In, Sign Up

Asminyl oral

Selected Xanthine Derivatives/Selected Macrolide Antibiotics

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

When these two medicines are taken together, your body may process the antibiotic more quickly. Also, your ability to process medicines called xanthine derivatives may slow down. Xanthine derivatives include caffeine and theophylline.

What might happen:

Your blood levels of antibiotic may decrease and reduce the ability of the medicine to treat your infection. Your blood levels of the xanthine derivative may increase and cause toxic effects.

What you should do about this interaction:

If you experience loss of appetite, nausea, vomiting, nervousness, agitation, headache, fast and/or irregular heartbeat, seizure, or worsening of your condition, contact your healthcare professional (e.g. doctor or pharmacist). This interaction may be worse if you have heart failure, liver disease, fluid on the lung, or are on large doses of theophylline.Your healthcare professionals may already be aware of this drug interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.


1.Prince RA, Wing DS, Weinberger MM, Hendeles LS, Riegelman S. Effect of erythromycin on theophylline kinetics. J Allergy Clin Immunol 1981 Dec; 68(6):427-31.
2.Pfeifer HJ, Greenblatt DJ, Friedman P. Effect of antibiotics on theophylline kinetics in humans. Clin Pharmacol Ther 1978 Jan;23(1):124-5.
3.Paulsen O, Hoglund P, Nilsson LG, Bengtsson HI. The interaction of erythromycin with theophylline. Eur J Clin Pharmacol 1987;32(5):493-8.
4.Reisz G, Pingleton SK, Melethil S, Ryan PB. The effect of erythromycin on theophylline pharmacokinetics in chronic bronchitis. Am Rev Respir Dis 1983 May;127(5):581-4.
5.Cummins LH, Kozak PP Jr, Gilllman SA. Erythromycin's effect on theophylline blood level. Pediatrics 1977;59(1):144-45.
6.Renton KW, Gray JD, Hung OR. Depression of theophylline elimination by erythromycin. Clin Pharmacol Ther 1981 Sep;30(3):422-6.
7.Zarowitz BJ, Szefler SJ, Lasezkay GM. Effect of erythromycin base on theophylline kinetics. Clin Pharmacol Ther 1981 May;29(5):601-5.
8.Iliopoulou A, Aldhous ME, Johnston A, Turner P. Pharmacokinetic interaction between theophylline and erythromycin. Br J Clin Pharmacol 1982 Oct;14(4):495-9.
9.LaForce CF, Miller MF, Chai H. Effect of erythromycin on theophylline clearance in asthmatic children. J Pediatr 1981 Jul;99(1):153-6.
10.May DC, Jarboe CH, Ellenburg DT, Roe EJ, Karibo J. The effects of erythromycin on theophylline elimination in normal males. J Clin Pharmacol 1982 Feb-Mar;22(2-3):125-30.
11.Adebayo GI, Adewumi MO, Mabadeje AF. Time-dependent inhibition of theophylline elimination by erythromycin stearate. Biopharm Drug Dispos 1986 Sep-Oct;7(5):479-85.
12.Branigan TA, Robbins RA, Cady WJ, Nickols JG, Ueda CT. The effects of erythromycin on the absorption and disposition of kinetics of theophylline. Eur J Clin Pharmacol 1981;21(2):115-20.
13.Richer C, Mathieu M, Bah H, Thuillez C, Duroux P, Giudicelli JF. Theophylline kinetics and ventilatory flow in bronchial asthma and chronic airflow obstruction: influence of erythromycin. Clin Pharmacol Ther 1982 May;31(5):579-86.
14.Kozak PP, Cummins LH, Gillman SH. Administration of erythromycin to patients on theophylline. J Allergy Clin Immunol 1977 Aug;60(2):149-51.
15.Stults BM, Felice-Johnson J, Higbee MD, Hardigan K. Effect of erythromycin stearate on serum theophylline concentration in patients with chronic obstructive lung disease. South Med J 1983 Jun;76(6):714-8.
16.Bartolucci L, Gradoli C, Vincenzi V, Iapadre M, Valori C. Macrolide antibiotics and serum theophylline levels in relation to the severity of respiratory impairment: a comparison between the effects of erythromycin and josamycin. Chemioterapia 1984 Oct;3(5):286-90.
17.Pasic J, Jackson SH, Johnston A, Peverel-Cooper CA, Turner P, Downey K, Chaput de Saintonge DM. The interaction between chronic oral slow-release theophylline and single-dose intravenous erythromycin. Xenobiotica 1987 Apr;17(4):493-7.
18.Pfeifer HJ, Greenblatt DJ, Friedman P. Effects of three antibiotics on theophylline kinetics. Clin Pharmacol Ther 1979 Jul;26(1):36-40.
19.Kimelblatt BJ, Slaughter RL. Lack of effect of intravenous erythromycin lactobionate on theophylline clearance. J Allergy Clin Immunol 1980 Apr; 65(4):313-4.
20.Vercelloni M, Cogo R, Albertini A, Granata M, Rosaschino F. Aminophylline blood levels with concomitant erythromycin therapy in relapsed chronic obstructive lung disease. J Int Med Res 1986;14(3):131-6.
21.Hildebrandt R, Gundert-Remy U, Moller H, Weber E. Lack of clinically important interaction between erythromycin and theophylline. Eur J Clin Pharmacol 1984;26(4):485-9.
22.Pingleton SK, Kelly SJ, Ryan PB. Lack of effect of erythromycin on theophylline serum levels. Chest 1980 Aug;78(2):352.
23.Maddux MS, Leeds NH, Organek HW, Hasegawa GR, Bauman JL. The effect of erythromycin on theophylline pharmacokinetics at steady state. Chest 1982 May;81(5):563-5.
24.Melethil S, Dutta A, Ryan PB, Pingleton SK, Kelly SJ. Steady state urinary excretion of theophylline and its metabolites in the presence of erythromycin. Res Commun Chem Pathol Pharmacol 1982 Feb;35(2):341-4.
25.Hildebrandt R, Moller H, Gundert-Remy U. Influence of theophylline on the renal clearance of erythromycin. Int J Clin Pharmacol Ther Toxicol 1987 Nov;25(11):601-4.
26.Wood MJ. The tolerance and toxicity of clarithromycin. J Hosp Infect 1991 Sep;19 Suppl A:39-46.
27.Weinberger M, Hudgel D, Spector S, Chidsey C. Inhibition of theophylline clearance by troleandomycin. J Allergy Clin Immunol 1977 Mar; 59(3):228-31.
28.Kamada AK, Hill MR, Brenner AM, Szefler SJ. Effect of low-dose troleandomycin on theophylline clearance: implications for therapeutic drug monitoring. Pharmacotherapy 1992;12(2):98-102.
29.Hopkins S. Clinical toleration and safety of azithromycin. Am J Med 1991 Sep 12;91(3A):40S-45S.
30.McConnell SA, Nafziger AN, Amsden GW. Lack of effect of dirithromycin on theophylline pharmacokinetics in healthy volunteers. J Antimicrob Chemother 1999 May;43(5):733-6.
31.Bachmann K, Jauregui L, Sides G, Sullivan TJ. Steady-state pharmacokinetics of theophylline in COPD patients treated with dirithromycin. J Clin Pharmacol 1993 Sep;33(9):861-5.
32.Bachmann K, Nunlee M, Martin M, Sullivan T, Jauregui L, DeSante K, Sides GD. Changes in the steady-state pharmacokinetics of theophylline during treatment with dirithromycin. J Clin Pharmacol 1990 Nov;30(11):1001-5.
33.Dal Negro R, Turco P, Pomari C, de Conti F. Miocamycin doesn't affect theophylline serum levels in COPD patients. Int J Clin Pharmacol Ther Toxicol 1988 Jan;26(1):27-9.
34.Principi N, Onorato J, Giuliani MG, Vigano A. Effect of miocamycin on theophylline kinetics in children. Eur J Clin Pharmacol 1987;31(6):701-4.
35.Couet W, Ingrand I, Reigner B, Girault J, Bizouard J, Fourtillan JB. Lack of effect of ponsinomycin on the plasma pharmacokinetics of theophylline. Eur J Clin Pharmacol 1989;37(1):101-4.
36.Shimizu T, Kato M, Mochizuki H, Takei K, Maeda S, Tokuyama K, Morikawa A. Roxithromycin attenuates acid-induced cough and water-induced bronchoconstriction in children with asthma. J Asthma 1997;34(3):211-7.
37.Bandera M, Fioretti M, Rimoldi R, Lazzarini A, Anelli M. Roxithromycin and controlled release theophylline, an interaction study. Chemioterapia 1988 Oct;7(5):313-6.
38.Saint-Salvi B, Tremblay D, Surjus A, Lefebvre MA. A study of the interaction of roxithromycin with theophylline and carbamazepine. J Antimicrob Chemother 1987 Nov;20 Suppl B:121-9.
39.Debruyne D, Jehan A, Bigot MC, Lechevalier B, Prevost JN, Moulin M. Spiramycin has no effect on serum theophylline in asthmatic patients. Eur J Clin Pharmacol 1986;30(4):505-7.

Be the first to share your experience with this drug.

Review this Treatment

Find a Drug:

by name or medical condition or shape/color (Pill Identifier)

(for example: aspirin)

(for example: diabetes)

Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Ask the pharmacist

Questions about medications? Get expert answers by video or live chat about allergies, pregnancy, sleep, and more.
See the Ask the Pharmacist event schedule.

Ask a Question

Popular Slideshows & Tools on WebMD

hands on abdomen
Can you catch one?
Woman sitting in front of UV lights
Is yours working?
woman using breath spray
What's causing yours?
womans hand on abdomen
Are you ready for baby?
MS Overview
Recognizing symptoms.
bowl of yogurt with heart shape
Eat for a healthy heart.
woman doing pushups
To help you get fit.
Colored x-ray of tooth decay
Know what to look for.
Woman sitting with child
Do you know the symptoms?
Stings, bites, burns, and more.
Allentown, PA
Are you living in one?
Thyroid exam
See how much you know.

Women's Health Newsletter

Find out what women really need.

WebMD the app

Get trusted health information. Whenever. Wherever... with your iPhone, iPad or Android.

Find Out More

IMPORTANT: About This Section and Other User-Generated Content on WebMD

The opinions expressed in WebMD User-generated content areas like communities, reviews, ratings, or blogs are solely those of the User, who may or may not have medical or scientific training. These opinions do not represent the opinions of WebMD. User-generated content areas are not reviewed by a WebMD physician or any member of the WebMD editorial staff for accuracy, balance, objectivity, or any other reason except for compliance with our Terms and Conditions. Some of these opinions may contain information about treatment or uses of drug products that have not been approved by the U.S. Food and Drug Administration. WebMD does not endorse any specific product, service, or treatment.

Do not consider WebMD User-generated content as medical advice. Never delay or disregard seeking professional medical advice from your doctor or other qualified healthcare provider because of something you have read on WebMD. You should always speak with your doctor before you start, stop, or change any prescribed part of your care plan or treatment. WebMD understands that reading individual, real-life experiences can be a helpful resource but it is never a substitute for professional medical advice, diagnosis, or treatment from a qualified health care provider. If you think you may have a medical emergency, call your doctor or dial 911 immediately.