Tiazac XC (Diltiazem) belongs to a class of medications called calcium channel blockers. Tiazac XC (Diltiazem) is used to treat mild to moderate high blood pressure and chronic stable Angina (chest pain). Tiazac XC (Diltiazem) works by relaxing blood vessels and by reducing the workload of the heart. It may take up to 2 to 4 weeks to see the full effects of Tiazac XC (Diltiazem).

Tiazac XC (Diltiazem) may be available under multiple brand names and/or in several different forms. Any specific brand name of Tiazac XC (Diltiazem) may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of Tiazac XC (Diltiazem) may not be used for all of the conditions discussed here.

Your doctor may have suggested Tiazac XC (Diltiazem) for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking Tiazac XC (Diltiazem), speak to your doctor. Do not stop taking Tiazac XC (Diltiazem) without consulting your doctor.

Do not give Tiazac XC (Diltiazem) to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take Tiazac XC (Diltiazem) if their doctor has not prescribed it.

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The usual recommended starting dose of Tiazac XC (Diltiazem) extended release tablets ranges from 180 mg daily to 240 mg daily. The maximum daily dose is 360 mg.

Tiazac XC (Diltiazem) should be taken once daily, at bedtime. It may be taken with or without food, but the way you take the medication should be consistent. Swallow the tablet whole with a glass of water – do not crush or chew the tablet.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take Tiazac XC (Diltiazem) exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store Tiazac XC (Diltiazem) at room temperature, protect it from moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of Tiazac XC (Diltiazem) with your doctor.

The following side effects have been reported by at least 1% of people taking Tiazac XC (Diltiazem). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• dizziness or lightheadedness
• flushing
• general feeling of being unwell
• headache
• heartburn
• nausea

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• irregular or fast, pounding heartbeat
• skin rash
• slow heartbeat
• swelling of ankles, feet, or lower legs
• symptoms of ear, nose, or throat infection (e.g., Fever, sore throat, cough inflammation of the nose or throat)
• unusual tiredness or weakness

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a severe skin reaction (e.g., blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort)
• symptoms of a serious allergic reaction (e.g., Hives, difficulty breathing, swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Tiazac XC (Diltiazem).

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120 mg
Each white, film-coated, extended-release tablet, debossed with "B" on one side, and the strength on the other, contains Tiazac XC (Diltiazem) HCl 120 mg. Nonmedicinal ingredients: carnauba wax, colloidal silicone dioxide, croscarmellose sodium, eudragit, hydrogenated vegetable oil, hydroxypropylmethylcellulose, magnesium stearate, microcrystalline cellulose, microcrystalline wax, polydextrose, polyethylene glycol, polysorbate, povidone, pregelatinized starch, simethicone, sodium starch glycolate, sucrose stearate, talc, and titanium dioxide.

180 mg
Each white, film-coated, extended-release tablet, debossed with "B" on one side, and the strength on the other, contains Tiazac XC (Diltiazem) HCl 180 mg. Nonmedicinal ingredients: carnauba wax, colloidal silicone dioxide, croscarmellose sodium, eudragit, hydrogenated vegetable oil, hydroxypropylmethylcellulose, magnesium stearate, microcrystalline cellulose, microcrystalline wax, polydextrose, polyethylene glycol, polysorbate, povidone, pregelatinized starch, simethicone, sodium starch glycolate, sucrose stearate, talc, and titanium dioxide.

240 mg
Each white, film-coated, extended-release tablet, debossed with "B" on one side, and the strength on the other, contains Tiazac XC (Diltiazem) HCl 240 mg. Nonmedicinal ingredients: carnauba wax, colloidal silicone dioxide, croscarmellose sodium, eudragit, hydrogenated vegetable oil, hydroxypropylmethylcellulose, magnesium stearate, microcrystalline cellulose, microcrystalline wax, polydextrose, polyethylene glycol, polysorbate, povidone, pregelatinized starch, simethicone, sodium starch glycolate, sucrose stearate, talc, and titanium dioxide.

300 mg
Each white, film-coated, extended-release tablet, debossed with "B" on one side, and the strength on the other, contains Tiazac XC (Diltiazem) HCl 300 mg. Nonmedicinal ingredients: carnauba wax, colloidal silicone dioxide, croscarmellose sodium, eudragit, hydrogenated vegetable oil, hydroxypropylmethylcellulose, magnesium stearate, microcrystalline cellulose, microcrystalline wax, polydextrose, polyethylene glycol, polysorbate, povidone, pregelatinized starch, simethicone, sodium starch glycolate, sucrose stearate, talc, and titanium dioxide.

360 mg
Each white, film-coated, extended-release tablet, debossed with "B" on one side, and the strength on the other, contains Tiazac XC (Diltiazem) HCl 360 mg. Nonmedicinal ingredients: carnauba wax, colloidal silicone dioxide, croscarmellose sodium, eudragit, hydrogenated vegetable oil, hydroxypropylmethylcellulose, magnesium stearate, microcrystalline cellulose, microcrystalline wax, polydextrose, polyethylene glycol, polysorbate, povidone, pregelatinized starch, simethicone, sodium starch glycolate, sucrose stearate, talc, and titanium dioxide.

Do not take Tiazac XC (Diltiazem) extended release tablets if you:

• are allergic to Tiazac XC (Diltiazem) or any ingredients of the medication
• are or may become pregnant
• have certain types of heart rhythm problems (sick sinus syndrome, or second or third-degree AV block) and do not use a pacemaker
• have fluid in the lungs due to severe heart failure
• have very Low Blood Pressure
• are taking the medication Dantrolene

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There may be an interaction between Tiazac XC (Diltiazem) extended release tablets and any of the following:

• Abiraterone acetate
• alpha blockers (e.g., Alfuzosin, Doxazosin, Silodosin, Tamsulosin)
• Aldesleukin
• Aliskiren
• alpha blockers (e.g., alfuzosin, doxazosin, tamsulosin)
• alpha agonists (e.g., Clonidine, methyldopa)
• Amiodarone
• amphetamines (e.g., Dextroamphetamine, lisdexamphetamine)
• anaesthetics
• angiotensin converting enzyme inhibitors (ACEIs; Captopril, Enalapril, Ramipril)
• angiotensin receptor blockers (ARBs; e.g., candasartan, Irbesartan, Losartan)
• anti-cancer medications (e.g., Cabazitaxel, Docetaxel; Doxorubicin; Etoposide, Ifosfamide, Irinotecan, Vincristine)
• Aprepitant
• Aripiprazole
• "azole" antifungals (e.g., fluconazole, ketoconazole, itraconazole)
• barbiturates (e.g., butalbital, pentobarbital, Phenobarbital)
• benzodiazepines (e.g., Lorazepam, Triazolam, midazolam)
• beta-adrenergic blocking agents (e.g., Atenolol, Labetalol, Metoprolol, Pindolol, Propranolol, Sotalol, Timolol)
• Bicalutamide
• boceprevir
• Bosentan
• brimonidine
• budesonide
• Buprenorphine
• Buspirone
• Busulfan
• Calcitriol
• Carbamazepine
• Carvedilol
• certain antipsychotics (e.g., Clozapine, Haloperidol, Quetiapine, Risperidone)
• certain protein kinase inhibitors (e.g., Dasatinib, imatinib, Nilotinib)
• chloroquine
• cilostazol
• Cimetidine
• Cobicistat
• colchicines
• Colestipol
• conivaptan
• Cyclosporine
• dantrolene
• Dapsone
• Deferasirox
• Dexamethasone
• Digoxin
• Flecainide
• Dipyridamole
• Disopyramide
• diuretics (water pills; e.g., Furosemide, Hydrochlorothiazide, triamterene)
• dofetilide
• Domperidone
• Donepezil
• Dronedarone
• Eletriptan
• Enzalutamide
• Eplerenone
• estrogens (e.g., conjugated estrogen, Estradiol, ethinyl estradiol)
• Ethosuximide
• Everolimus
• felbamate
• Fingolimod
• Galantamine
•  “gliptin” diabetes medications (e.g., Linagliptin, Saxagliptin, Sitagliptin)
• grapefruit juice
• Guanfacine
• HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., delaviridine, efavirenz, etravirine, nevirapine)
• HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
• Lacosamide
• Lanreotide
• levodopa
• lidocaine
• lithium
• Lomitapide
• macrolide antibiotics (e.g., clarithromycin, erythromycin)
• magnesium supplements
• maraviroc
• Mefloquine
• mestranol
• Methadone
• methyldopa
• Methylphenidate
• Metronidazole
• Minoxidil
• mifepristone
• Mirtazapine
• Modafinil
• monoamine oxidase inhibitors (M.O.S. e.g., Moclobemide, Phenelzine, Rasagiline, Selegiline, Tranylcypromine)
• Montelukast
• narcotic pain relievers (e.g., Codeine, Fentanyl, Morphine, Oxycodone)
• Nateglinide
• nefazodone
• nitrates (e.g., isosorbide dinitrate,  isosorbide mononitrate)
• Norfloxacin
• Octreotide
• Ondansetron
• other calcium channel blockers (e.g., Amlodipine, Tiazac XC (Diltiazem), Nifedipine, Verapamil)
• Pasireotide
• Pazopanib
• Pentoxifylline
• Perampanel
• Phenytoin
• phosphodiesterase-5 inhibitors (e.g., Sildenafil, Tadalafil, Vardenafil)
• Pimozide
• praziquantel
• Primaquine
• primidone
• procainamide
• progestins (e.g., Dienogest, Levonorgestrel, medroxyprogesterone, Norethindrone)
• Propafenone
• proton pump inhibitors (e.g., Lansoprazole, Omeprazole)
• quinidine
• quinine
• Repaglinide
• rifabutin
• rifampin
• rilpivirine
• Rituximab
• Rivaroxaban
• Rivastigmine
• Romidepsin
• St. Johns wort
• salmeterol
• saxagliptin
• selective serotonin reuptake inhibitors (SSRIs; e.g., Citalopram, Duloxetine, Fluoxetine, Paroxetine, Sertraline)
• simeprevir
• Sirolimus
• sitaxentan
• statin medications (e.g., Atorvastatin, Simvastatin)
• Tacrolimus
• Tamoxifen
• telaprevir
• Temsirolimus
• Tetracycline
• Theophylline
• Ticagrelor
• Ticlopidine
• Tizanidine
• Tocilizumab
• Tolterodine
• Tolvaptan
• Tramadol
• Trazodone
• tricyclic antidepressasnts (e.g., Amitriptyline, Clomipramine, Desipramine, Trimipramine)
• Trimethoprim
• Venlafaxine
• Warfarin
• Zolpidem
• Zopiclone

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Tiazac XC (Diltiazem). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.

Blood pressure: Occasionally, blood pressure drops too low after taking Tiazac XC (Diltiazem). Tiazac XC (Diltiazem) extended release tablets may cause dizziness and a drop in blood pressure when you stand from a sitting or lying down position, especially if you are taking medications that lower blood pressure. Get up slowly from a sitting or lying down position while you are taking this medication. If you experience lightheadedness, weakness, or dizziness, talk to your doctor.

Congestive Heart Failure: Tiazac XC (Diltiazem) extended release tablets may make symptoms of congestive heart failure worse. If you have congestive heart failure, discuss with your doctor how Tiazac XC (Diltiazem) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Diabetes: Tiazac XC (Diltiazem) extended release tablets may cause an increase in blood glucose. People with diabetes may find it necessary to monitor their blood sugar more frequently while using Tiazac XC (Diltiazem). If you have diabetes or are at risk for developing diabetes, discuss with your doctor how Tiazac XC (Diltiazem) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Tiazac XC (Diltiazem), and whether any special monitoring is needed.

Heart rhythm problems: In people with certain types of heart rhythm problems (e.g., sick sinus syndrome, second- and third-degree atrioventricular block), Tiazac XC (Diltiazem) extended release tablets may cause abnormally slow heart rates. If you have one of these heart rhythm problems, discuss with your doctor how Tiazac XC (Diltiazem) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Tiazac XC (Diltiazem), and whether any special monitoring is needed.

If you have heart rhythm problems, do not use Tiazac XC (Diltiazem) if you do not use a pacemaker.

Kidney function: If you have reduced kidney function or Kidney Disease, discuss with your doctor how Tiazac XC (Diltiazem) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Tiazac XC (Diltiazem), and whether any special monitoring is needed.

Liver function: Liver disease or reduced liver function may cause Tiazac XC (Diltiazem) to build up in the body, causing side effects. If you have reduced liver function or liver disease, discuss with your doctor how Tiazac XC (Diltiazem) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Tiazac XC (Diltiazem), and whether any special monitoring is needed. Your doctor will monitor your liver function closely while you are taking Tiazac XC (Diltiazem).

Tiazac XC (Diltiazem) extended release tablets may cause a decrease in liver function. If you experience symptoms of liver problems (itchy rash, yellowing of the eyes or skin, dark urine, vomiting, upper right abdominal pain), stop taking Tiazac XC (Diltiazem) and contact your doctor immediately.

Pregnancy: Tiazac XC (Diltiazem) should not be used during pregnancy. If you become pregnant while taking Tiazac XC (Diltiazem), contact your doctor immediately.

Breast-feeding: Tiazac XC (Diltiazem) passes into breast milk. If you are a breast-feeding mother and are taking Tiazac XC (Diltiazem), it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using Tiazac XC (Diltiazem) have not been established for children.

Seniors: People 65 years or older may experience more side effects than younger people. Your doctor will monitor you closely while you are taking Tiazac XC (Diltiazem).

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