The People's Perspective on Medicine



Cardizem CD belongs to a class of medicines called calcium channel blockers. Because of their safety and effectiveness, these drugs have helped revolutionize the treatment of angina and high blood pressure.

Cardizem CD is prescribed to treat high blood pressure alone or in combination with other blood pressure pills. It is also helpful for certain forms of angina.

Other brand names for diltiazem include Cardizem SR, Dilacor XR and Tiazac.

Side Effects and Interactions

Cardizem CD is usually well tolerated with few side effects, but some people react to this drug with fluid retention, leading to swelling of the legs, feet or hands. Headache, dizziness, loss of strength, slowed heart rate, heart problems or flushing may also occur.

Other side effects include nausea, rash, constipation, increased blood sugar, sexual difficulties and depression.

The skin may be especially sensitive to sunburn, and precautions should be taken to avoid ultraviolet exposure. Report any symptoms or suspected side effects to your physician promptly.

Cardizem CD can interact with a number of other drugs, including several that are used to treat high blood pressure or heart conditions, the anticonvulsant Tegretol, the ulcer medicine Tagamet, lithium and the transplant drug Sandimmune.

The herb St. John’s wort might speed elimination of diltiazem from the body, which could reduce its effectiveness.

Check with your doctor and pharmacist to make sure Cardizem CD is safe in combination with any other drugs or herbs you take.

Special Precautions

People with liver or kidney disease should take Cardizem CD under close medical supervision and monitoring.

Some people may feel dizzy if they sit or stand up suddenly. Low blood pressure or a recent heart attack also signal serious problems.

Taking the Medicine

Cardizem CD may be taken with or without meals, once a day.

Do not stop taking Cardizem CD suddenly, as this could lead to complications. Your doctor will tell you how to taper off gradually if you no longer need this medication.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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I am having major breathing issues. Chronic cough with phelgm night and day. Wake up middle of night. For several monnths of year. Been on Diltiazem for 4 to 5 years. Stopping for 4 days to see if cough stops as per doctor.

I recently stopped my diltiazem without doctors orders. I have been eating right and exercising and the only problem is my fast rate every now and then. My pulse is between 97-107. I checked my blood pressure and I’ve got it down to 120/89. I will follow up with my Dr but I believe over time my heart will be back to normal.

I am on Medicaid, and the pharmacy HAS to give me generics….if unavailable, the dr. has to use something else….Medicaid is horrible. I think people should know that they are not giving good coverage.

I experienced these side effects with Diltiazem (generic) when my generic was changed. I had taken Dil for several years without problems. Although it took me a while to realize the problems with my feet and legs were related to the new RX, I can trace their beginnings to the new generic.
Despite the FDA claims that generics are comparable to the branded product, they are not. I made it a point to be sure I was getting the same generic each time I filled my RX. Unfortunately, the one I was using was no longer available at my pharmacy. I had to call around only to find that generic is not available locally.
Too many things factor into the generics we receive, but price is the major factor that determines which generics are stocked. Efficacy and side effects are not.

I recently got Abalation for my SVT fast heart beat, have been off of Dilitiazem for five days and feel so much better. it was affecting my lungs, couldn’t breath very well. I am surprised that I am kind of the lone ranger with my lung problem through taking Dilitiazem. I have stopped it entirely and feel 100 per cent better.
Are there any others who have had a lung problem while taking ?

When you got this ablation, were there any complications?

hey bill, are you still off the ccbs for svt ? How are you doing after the ablation?
I was also daignosed with SVT. Thanks

MIralax solved it for me. I have to use it every day. Resolved it within two or three days and problem has not returned.

About Diltiazem and fatigue, 75-year old male.
I went in for knee replacement in March. Woke up in ICU 3 or 4 days later with bad pneumonia. Apparently had very low blood oxygen which triggered the ICU visit. Have had Afib ever since. Tried Metoprolol for a while, little change and very fatigued. Tried cardioversion – twice – both failed after a few hours.
After a week of no drugs, went onto 300mg Diltiazem, 20mg Flecainide 2x, and one more cardioversion. This one worked, but I’d be out of breath after climbing one flight of stairs. Complained of extreme fatigue, doctor started reducing Cardiozem from 300 to 240 to 120 to 120 every other day, Energy came back, mostly, depression ebbed, and creativity started coming back.
A week ago I stopped Cardiozem totally on my initiative, but still on Flecainide twice a day. Fatigue has disappeared, I can walk a mile with no problems, no Afib except for occasional missed beats. There are times when a super-deep breath seems to cause a skipped beat, but I’m pleased with present situation. I attribute loss of creativity, interest in life, and abnormal fatigue to Diltiazem. Maybe it’s one of many bad alternatives, but Diltiazem worked for me.

Oh, I see, yvonne….no, this is not a “constipation” that can be solved with dietary measures….I had to go off of the drug.

How are you feeling now? Can you let me know? Thanks.


I began prescribed DILTIZEM one week ago for angina. The first night I took my 120 mgs 24HR extended release capsule. It seemed I got an almost immediate headache within about 1 hour of swallowing it. And it was a bad headache. The bad headache made me nauseous. The next morning I still had the bad headache and knew I could not get started on the path of bad headaches with any luck. So I checked with my pharmacist about the safety of taking a couple Excedrin to relieve the headache. Being the Excedrin has Caffiene etc the pharmacist suggested that instead I take Tylenol. Nothing Happened. Still a very bad headache throughout the day:(
Late noon I decided to try the Excedrin. Within two hours my headache was gone and has not been back. So the second night I took my DILTIZEM and up to present one week later no headaches have revisited. AND I am getting 75percent relieve of my angina symptoms which I’ve had the past 6 plus months. No other side effects as yet but I realize I am on a low dose of the med. I also do not want to increase it….

Can you please tell me how you got of Diltiazem?

I am researching diltiazem, having been given the option today of that, or no rx whatsoever for something. I say, “for something,” because it was a quick MD visit – it is perhaps cardiac related. Anyway, my thought about your subacute thyroidits and the CCB is extremely hypothetical – wouldn’t the thyroiditis be short-term, and treatment be very short term? I ask, because I wonder if the subacute thyroiditis – and how did the doc get to that diagnosis – has resolved, so you are experiencing the effects of taking an rx that you do not need. ?

I was started on Diltiazem recently, after deciding that the Dyazide (sp?) I had been on for several years caused my blood calcium levels to increase dramatically (which caused a whole other host of negative symptoms/side effects!). My doc started me on the Diltiazem at 180 mg Extended Release. I was told this med is a calcium channel blocker.
After 2 weeks, I could barely walk – I was SO fatigued – my body felt like it weighed 500 pounds (with each leg weighing at least 100 pounds!!) … I couldn’t get out of bed in the morning, and once at work, I could barely stay awake – I felt like I needed a nap every hour. It’s a living hell trying to get through 8-1/2 hours of work (and a half-hour each way to get there), when you are feeling like this! I would get up in the morning, and an hour later be on my way to work, with my eyes practically shutting on their own – as if I had narcoplepsy or something!
How can you sleep for 8 hours (I don’t have trouble sleeping – I take Ambien, so I know I was staying asleep all night), then get up, and an hour later feel like you’re so tired, as if you’ve been awake for the last 18 hours?? Another side effect was that I got horribly depressed – I almost felt suicidal. I say “almost,” because I don’t have enough guts to actually do it (and I’d never do that to my kids). But I was begging God to take my life – that is how horrible I felt. I didn’t feel like doing anything, and didn’t know what to do with myself. My mind felt like it was “going crazy,” and I didn’t know or couldn’t explain “why.”
I was completely baffled as to why I was feeling so weird. Sitting on the couch all day long (after work and on the weekends) made me feel so horrible. Some of those days I would sit and cry on and off, either all evening or all day, for no apparent reason (depending on the day of the week and whether I had worked all day or not).
2 weeks after starting the Diltiazem, I started taking Cytomel – after many years of being on synthroid with seemingly no relief (of the fatigue I had always had), I finally got the nerve to ask my doc if I could try adding this medication (due to reading others’ postings on how adding this medication made a world of difference). After being on this for a week, I started experiencing horrible hot flashes. So a few days later, I quit taking both the Diltiazem and the Cytomel. Within 3 days, ALL the negative, horrible symptoms I had been experiencing disappeared.
I didn’t want to give up on the Cytomel, so after a week or 10 days of being off both meds (my doctor and his office are all currently on vacation until the 15th of July, so I can’t call or see him), I decided I did not want to give up on the Cytomel just yet, and started taking it again. I’ve taken it for about 5 days now, and have not gotten the hot flashes back yet, nor any of the other “negative” side effects. So I think they were all a result of the Diltiazem.
When I first started experiencing the severe fatigue (about a week after starting the Diltiazem), I asked the pharmacist if this medication could be the cause, and she said that yes, it can cause fatigue, especially if the dose is too high (which makes me question if my doc should have started me on a lower dose – but I’m sure he started me at this dose because my blood pressure is quite high, so I’m not saying he is wrong). But maybe I needed to ease my way into the higher dose? But now, I am very, very leery about going back on this medication. I’m telling you – I never felt so low and depressed in my life – and felt like I was going crazy.
My sister is a surgical nurse, and she said, “Oh, those blood pressure meds are bad news – they make people feel like sh—!” And she meant ANY BP medication. So what are we to do? I am a little overweight … so I guess I’m going to try walking and shedding some pounds. Plus, I had been taking Adderall (for my extreme fatigue), which I’m sure is at least half the cause of my high BP. But I quit the Adderall several months ago, precisely because of my high BP. Only to have my severe fatigue DOUBLE after going on the Diltiazem!! I am also going to try the Aloe Vera that one of the posters suggested.
So, due to what I’ve been told by the pharmacist and my R.N. sister, Diltiazem (as well as all other BP meds) make people feel really crappy, and cause a whole bunch of negative side effects!
People’s Pharmacy response: Your sister overgeneralized, we think. It can be hard to find a blood pressure medicine that you can tolerate, but usually it is possible.

I’m on Diltiazem too following AFs and high blood pressure. It controls my bp but makes me very depressed. I am sure it is this drugs. beta blockers give me asthma. I still get AFs and take flecanide too, that drug gives me low mood too. any suggestion?

if you really have high blood pressure, please be careful about stopping CCBs abruptly. my pharmacist says it could cause a heart attack or stroke. I wish I knew the answer to high blood pressure… if diet and exercise work for you, you are very lucky. for a lot of us, it’s genetic (parents and GP died in 60s).

RM – I was having some of the same issues. Very bad insomnia, would wake up the same time each night. have been off Diltiazem for 2 days now and sleeping like a baby! I was having the same issue of sleeping on my left side. Right was much better for me or back. I also developed bronchitis after a few weeks and since I’ve been off I’m feeling better. I’m also regaining my energy!!

I recently was diagnosed with subacute thyroiditis. My doctor initially put me on beta-blockers for symptomatic relief, but I had a slight allergic reaction and I was put on Diltiazem 120mg instead. Everything was okay for a while, but in the past week I have been experiencing really bad insomnia. I get a pain in my chest when I try to sleep on my left side and sometimes even my right. I am forced to just sleep on my back.
During this time the tinnitus in my ears has gotten worse and I have been experiencing trouble concentrating and focusing on things. Could this be due to the Diltiazem? Thank you.

I too am on Diltiazem. I’m very sensitive to all medications. Before Diltiazem I was on Diovan for my MVP and high blood pressure. After being on Divoan for 4-5 years I ended up with drug induced edema and was taken off immediately. My cardiologist said only 1% of people get this. Now that I’m on Diltiazem I feel so tired, no energy and I’ve had bronchitis for 3 weeks now. I just wonder if my cough and bronchitis is from the Diltiazem. What is also very strange is my blood pressure is very high being on this medication.
When I stopped the Diovan for awhile and not on any meds my blood pressure was normal. I tried to stop taking my Diltiazem and I was getting chest pains. Never had chest pains in my life. So maybe this is withdrawal symptoms?

Aloe Vera. Get it at your local health food store. Make sure it is a liquid and make sure it says whole leaf. I think the stuff with the pulp works better but it is hard to find. It tastes a little sour like lemon, but not as intense and a little “green” like juiced wheatgrass. Aleo Vera 2 x a day and things will be flowing great in a few days to a week.

It has taken almost two years to get the medication right. During that time, I felt horrible, had gastric problems, at times had such leg pain that I couldn’t walk, and multiple arrhythmias. It started with an episode of rapid atrial flutter and maybe, the docs aren’t sure, a short run of atrial fibrillation. Suddenly I had high blood pressure also.
Went from no drugs to 3: beta blocker, ASE inhibitor, diuretic. I thought I was going to die. Lived on the sofa for weeks, coughing. Drugs were started and stopped. Cardizem gave me long runs of ventricular bigemini and finally heart block with a rate of 32. I don’t think it is good to slow a heart down when the base rate is 58 without drugs!
Started ARBs, Benicar, but insurance wouldn’t cover it, so I tried Micardis and got bad gastric problems. Insurance now covers Benicar, works ok, had to increase it when Cardizem was stopped. Was on HCTZ for awhile, felt bad and had more gastric problems. Also, have hip bursitis and got a steroid injection. They might say it doesn’t affect your BP, but mine went up 50 for a week.

what in the world can be done about the horrible constipation?? thnx

Thank you for your comments. This gives me hope that my depression, anxiety and memory problems are indeed caused by first Metroprolol and now Diltiazem. I have good information to give my doctor tomorrow.

I was on the beta blocker metoprolol at first for about six months, but I didn’t like the sluggish and very depressed feeling it gave me. I switched to diltiazem about four months ago and it’s better, but still not good. I’m a professional writer and haven’t been able to write anything except for articles (no personal essays) since starting all these medicines 10 months ago. I definitely think that both metoprolol and also diltiazem lower/suppress creativity. Maybe the lowered creativity is a function of depression. Anyway, I’m getting ready to ask my cardiologist if I can try stopping the diltiazem altogether.

Psvt and pvc’s and wide complex tachycardia have ruined my life. They have tried an ablation but they do not know where or what is causing the problems. I was on flecainide for a while and it did not set well with my body, had several side effects. Back in june I was put on cardizem and now my dr refuses to fill it and I am forced to quit taking it abruptly. I feel weak, tired, and shaky, anyone ever had this problem?

Is it common for Diltiaziem to cause leg fatigue and in general tiredness? Been on it since the spring and I swear my legs have been more fatigued.

All I know is that it is not a bad idea to get another opinion.
:) I had psvt at 315 beats per minute. An ablation was done and it worked …6 months later I had another ablation for an abundance of pbc’s. 3 months later I had an ep study but they only found I had sinus tech. Now its been 10 months since then and I have a new problem in my heart but the doctors can’t figure it out. It starts with really bad chest pain and leads to an icy cold left ARM and especially my hand and finger tips.
So my doctor flat out told me he knows there is something serious going on, but ” I don’t know what is wrong with you” so he put me on diltiazem (which is medicine for heart spasms) and told me to come back in 2 months. The punch line is non of my symptoms or history give cause for heart spasms and he told me that were just gonna out of the blue try it. Then in 2 months if it isn’t successful were going through tons of tests and possibly the mayo clinic.
So a second opinion would not hurt! :) no need to live life with 1 solution causing another problem. I wish the best for you…. and I am a 20 year old female, believe it or not but my surgery was done when I was18 and 19 yo. :)

One year ago I had a fast heart beat – 220 beats per minute. Went to emergency room and doctor said I had AVNRT and he said that he could fix it with ablation procedure and I agreed. All of my other tests were normal blood work, cholesterol, no blockage, etc. After that my heart rate went back to normal – “Hooray!” The doctor came into my room the next day after an EKG and pointed at me and said “You’re cured!” Thanks, Doc, I said with exclamation, and went home.
Well, 14 days later my SVT’s came back – 220 beats per minute. I went back to the E.R. They stopped my heart twice with drugs and it didn’t work so they shocked me, twice. That also didn’t work so they gave me a Diltiazem injection and that worked to slow my heart rate. But my heart rate was irregular and they sent me home with a prescription of Diltiazem, 240 mg. and a Halter monitor, and an appointment in 3 weeks with another doctor. As I was taking my medication, it made me sick in my stomach.
I made my appointment and the doctor entered the room and said, Hello, what can I do for you? I replied I had an ablation that did not work and this was a follow up on medication and Halter monitor results. This was about 5 weeks post-ablation. So he opened my file and started reading it while I sat there. He said ok, I see. So he hooked me up and told me that I had an irregular heartbeat and told me to go to the E.R., so I did. In the E.R., my cardiologist came in and asked “What are you doing here?” So I told him. He increased my medication to 360 mg. I told him the medication made me sick to my stomach and he said o.k. and sent me home. He ordered an event monitor but none were available, and advised to pick one up at a later date and approximately 6 weeks later one was available.
But in the meantime, my heart rate returned to normal in about 2 weeks. I went to get the monitor and the nurse told me to push the button when I had an event. I explained that I did not have any events in a while, and that my heart rhythm was normal for about 4 weeks, and that they should use the monitor for someone that needed it and she did. After that it was 6 weeks until I went back to see the cardiologist and told him that I believed my ablation finally worked because my heart rate was back to normal, no irregular heart beat, and that I wanted to reduce my medication to see.
The same doctor that told me that I was cured looked at me and said, your ablation did NOT work, it’s the medication! I said the medication makes me feel sick to my stomach. He asked me if I had heard of that saying “If it ain’t broke, don’t fix it” – take your meds and come back to see me next year, which was over 6 months later. So like a good patient, I took my meds, 360 mg. for three months, and they still made me sick with no irregular heartbeat.
So I decided if the doctor wouldn’t, I would. So I started tapering off my meds from 360 to 300 to 250 to 200 to 150 and now to 100 mg. I was wondering if I should stop altogether. I have read a lot of articles on ablation therapy and most said that it can take about a year for the full effects of ablation to work in some people and others told of the effects of liver and kidney damage from the medication that I am taking. Does anyone know if I should change my doctor or get off the
medication altogether???
Now my blood pressure is a little high (always normal before ablation) and I was wondering if it is because my body is used to the high blood pressure medication they had me on and if that was the cause of my blood pressure being high from my body reacting negatively as withdrawal symptoms from tapering off this medication and does my body just need time to adjust? By the way I’m a 60 year old man .

After taking diltiazem for four years, I suddenly started getting very intense hot flashes around the clock. I tried Remifemin which worked for about a month when the hot flashes returned at full force. I finally realized my hot flashes were fairly regular every 2 hours or so with a feeling of a major adrenaline release just prior to me heating up to the boiling point.
After doing some research, I decided to try stopping the time-released drug, diltiazem. I had an immediate reduction in hot flashes with a full stop after about a week and a half, once the drug was out of my system. Constipation is gone, skin discoloration is fading, depression has lifted, blood sugar sensitivity has decreased and I’m finally able to lose weight gained during this four-year period. I was blaming these side effects on quitting smoking three years ago, but obviously they were actually caused by the diltiazem.

After several pretty high blood pressure readings, my primary care doctor insisted I take blood pressure medication. We started with hydrochlorothiazide which gave me severe foot and leg cramps which disturbed my sleep. Next she tried me on a calcium channel blocker, amlodipine, which gave me intense hot flashes right away. The second calcium channel blocker, diltiazem, gave me intense hot flashes after about 5 days.
Within a week I was getting no sleep at all. After 8 days I stopped the diltiazem, and the number of hot flashes are slowly diminishing. My primary care doctor says the next step is a beta blocker which she guarantees will have sexual side effects. From everything I have read they also just about guarantee fatigue and depression which I already have on account of taking Arimidex, an aromatase inhibitor, for metastatic breast cancer.
I have looked at all the classes of blood pressure meds, and all of them have unacceptable side effects. I am pretty fed up with prescription medications. Since my blood pressure seems to be staying at an acceptable level, I’m going to treat myself with diet, exercise and garlic.

I have really noticed an increase in my blood sugar as well on Cardizam. We were thinking it was the fluid pill that was added in conjunction with the BP med. Or, the fact that I switched from Lantus to Levemir, but I got off the fluid pill and sugar has continued to increase. I’ve reacted to several blood pressure meds and we are really having a hard time finding an effective one with no reactions. We’ll keep working on it, I’m sure. Good luck with your sugar issues.

I am an insulin diabetic… started on cardizem 4 wks ago… my blood sugar has increased to the point that I have doubled the amt. of insulin and still having trouble controlling it.

Ask your doctor if you can take a cardioselective beta blocker. They do exist and won’t affect your lungs. As far as bp med, there are tons of them. Keep trying different combos until one works for you.

WOW…. I heard that if you get more than 4 meds going you are going to have side effects. I too am a little sensitive to certain med. I can’t take any beta blockers (for arrhythmia) they affect my lungs and breathing.Try low salt diet and walking or rebounding (mini-trampoline) whatever, get moving so you can come off most of these meds!!

My doctor has prescribed 8 different bp meds including Benicar, Micardis, Tarka, Coreg, Bystolic, Toprol, Dynacirc, & Cartia. The side effects were so debilitating that I was unable to tolerate them for any length of time. Does anyone have advice?

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