Skip to content
My WebMD Sign In, Sign Up

Dilacor XR oral

Cyclosporine/Calcium Channel Blockers

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:

The cause of the interaction is not known. When these two medicines are taken together, your calcium channel blocker may prevent your body from processing cyclosporine properly.

What might happen:

Your blood levels of cyclosporine may increase and cause toxic effects.

What you should do about this interaction:

Contact your doctor if you experience headache; dizziness; blurred vision; weakness; fatigue; unusual hair growth; swelling of the ankles, feet or hands; irregular or fast heartbeat; muscle pain; nausea; stomach pain; yellowing eyes or skin; dark urine; fever; numbness or tingling of the hands or feet; changes in amount of urine; constipation or diarrhea; or shortness of breath. It may be necessary to adjust your dose of cyclosporine or change you to a different medicine.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this 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.Wagner K, Neumayer HH. Prevention of delayed graft function in cadaver kidney transplants by diltiazem. Lancet 1985 Dec 14;2(8468):1355-6.
2.Pochet JM, Pirson Y. Cyclosporin-diltiazem interaction. Lancet 1986 Apr 26;1(8487):979.
3.Grino JM, Sabate I, Castelao AM, Alsina J. Influence of diltiazem on cyclosporin clearance. Lancet 1986 Jun 14;1(8494):1387.
4.Bourbigot B, Guiserix J, Airiau J, Bressollette L, Morin JF, Cledes J. Nicardipine increases cyclosporin blood levels. Lancet 1986 Jun 21; 1(8495):1447.
5.Neumayer HH, Wagner K. Diltiazem and economic use of cyclosporin. Lancet 1986 Aug 30;2(8505):523.
6.Lindholm A, Henricsson S. Verapamil inhibits cyclosporin metabolism. Lancet 1987 May 30;1(8544):1262-3.
7.Cantarovich M, Hiesse C, Lockiec F, Charpentier B, Fries D. Confirmation of the interaction between cyclosporine and the calcium channel blocker nicardipine in renal transplant patients. Clin Nephrol 1987 Oct; 28(4):190-3.
8.Maggio TG, Bartels DW. Increased cyclosporine blood concentrations due to verapamil administration. Drug Intell Clin Pharm 1988 Sep;22(9):705-7.
9.Wagner K, Henkel M, Heinemeyer G, Neumayer HH. Interaction of calcium blockers and cyclosporine. Transplant Proc 1988 Apr;20(2 Suppl 2):561-8.
10.Henricsson S, Lindholm A. Inhibition of cyclosporine metabolism by other drugs in vitro. Transplant Proc 1988 Apr;20(2 Suppl 2):569-71.
11.Kohlhaw K, Wonigeit K, Frei U, Oldhafer K, Neumann K, Pichlmayr R. Effect of the calcium channel blocker diltiazem on cyclosporine A blood levels and dose requirements. Transplant Proc 1988 Apr;20(2 Suppl 2):572-4.
12.Kessler M, Netter P, Renoult E, Jonon B, Mur JM, Trechot P, Dousset B. Influence of nicardipine on renal function and plasma cyclosporin in renal transplant patients. Eur J Clin Pharmacol 1989;36(6):637-8.
13.McNally P, Mistry N, Idle J, Walls J, Feehally J. Calcium channel blockers and cyclosporine metabolism. Transplantation 1989 Dec; 48(6):1071.
14.McFadden JP, Pontin JE, Powles AV, Fry L, Idle JR. Cyclosporin decreases nifedipine metabolism. BMJ 1989 Nov 11;299(6709):1224.
15.Kelly JJ, Walker RG, d'Apice AJ, Kincaid-Smith P. A prospective study of the effect of diltiazem in renal allograft recipients receiving cyclosporine A: preliminary results. Transplant Proc 1990 Oct; 22(5):2127-8.
16.Tortorice KL, Heim-Duthoy KL, Awni WM, Rao KV, Kasiske BL. The effects of calcium channel blockers on cyclosporine and its metabolites in renal transplant recipients. Ther Drug Monit 1990 Jul;12(4):321-8.
17.Bourge RC, Kirklin JK, Naftel DC, Figg WD, White-Williams C, Ketchum C. Diltiazem-cyclosporine interaction in cardiac transplant recipients: impact on cyclosporine dose and medication costs. Am J Med 1991 Mar; 90(3):402-4.
18.Dy GR, Raja RM, Mendez MM. The clinical and biochemical effect of calcium channel blockers in organ transplant recipients on cyclosporine. Transplant Proc 1991 Feb;23(1 Pt 2):1258-9.
19.Tenschert W, Harfmann P, Meyer-Moldenhauer WH, Arndt R, Klosterhalfen H. Kidney protective effect of diltiazem after renal transplantation with long cold ischemia time and triple-drug immunosuppression. Transplant Proc 1991 Feb;23(1 Pt 2):1334-5.
20.Endresen L, Bergan S, Holdaas H, Pran T, Sinding-Larsen B, Berg KJ. Lack of effect of the calcium antagonist isradipine on cyclosporine pharmacokinetics in renal transplant patients. Ther Drug Monit 1991 Nov; 13(6):490-5.
21.Kunzendorf U, Walz G, Brockmoeller J, Neumayer HH, Jochimsen F, Roots I, Offermann G, Strom TB. Effects of diltiazem upon metabolism and immunosuppressive action of cyclosporine in kidney graft recipients. Transplantation 1991 Aug;52(2):280-4.
22.Chagnac A, Zevin D, Ori Y, Korzets A, Hirsh J, Levi J. The effect of high-dose nifedipine on renal hemodynamics of cyclosporine-treated renal allograft recipients. Transplantation 1992 Apr;53(4):766-9.
23.Leibbrandt DM, Day RO. Cyclosporin and calcium channel blockers: an exploitable drug interaction?. Med J Aust 1992 Sep 7;157(5):296-7.
24.Chrysostomou A, Walker RG, Russ GR, d'Apice AJ, Kincaid-Smith P, Mathew TH. Diltiazem in renal allograft recipients receiving cyclosporine. Transplantation 1993 Feb;55(2):300-4.
25.Kuzuya T, Kobayashi T, Moriyama N, Nagasaka T, Yokoyama I, Uchida K, Nakao A, Nabeshima T. Amlodipine, but not MDR1 polymorphisms, alters the pharmacokinetics of cyclosporine A in Japanese kidney transplant recipients. Transplantation 2003 Sep 15;76(5):865-8.
26.Pesavento TE, Jones PA, Julian BA, Curtis JJ. Amlodipine increases cyclosporine levels in hypertensive renal transplant patients: results of a prospective study. J Am Soc Nephrol 1996 Jun;7(6):831-5.
27.Sennesael J, Lamote J, Violet I, Tasse S, Verbeelen D. Comparison of perindopril and amlodipine in cyclosporine-treated renal allograft recipients. Hypertension 1995 Sep;26(3):436-44.
28.Cardizem LA (diltiazem hcl extended release tablets) US prescribing information. Abbott Pharmaceuticals, Inc. November, 2010.

See 8 Reviews for this Drug. - OR -

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.