Drug Interactions between Diltiazem Hydrochloride XR and perindopril

Alcohol can lower your blood pressure and add to the effects of dilTIAZem. You may experience dizziness, lightheadedness, fainting, or a rapid heartbeat if you drink alcohol with dilTIAZem, especially when you first start taking the medication or just after a dose increase. Grapefruit juice may also increase the effects of dilTIAZem in some people by increasing its levels in the blood. You may want to limit alcohol intake and avoid excessive consumption of grapefruit and grapefruit juice during treatment with dilTIAZem. However, if you have been regularly consuming grapefruit or grapefruit juice with dilTIAZem, do not alter the amounts of these products in your diet without first talking to your doctor or other healthcare professional. Contact your doctor if your condition changes or you experience increased side effects of dilTIAZem such as headache, irregular heartbeat, swelling, unexplained weight gain, or chest pain. Orange juice is not expected to interact.

Consumer information for this interaction is not currently available.

GENERALLY AVOID: Moderate-to-high dietary intake of potassium can cause hyperkalemia in some patients who are using angiotensin converting enzyme (ACE) inhibitors. In some cases, affected patients were using a potassium-rich salt substitute. ACE inhibitors can promote hyperkalemia through inhibition of the renin-aldosterone-angiotensin (RAA) system.

ADJUST DOSING INTERVAL: Administration with food decreased the biotransformation of perindopril to its active metabolite, perindoprilat, resulting in a decrease of perindoprilat bioavailability by 35% and a reduction in the plasma ACE inhibition curve of approximately 20%. When administered as part of a combination product with amlodipine and taken with food, perindopril and perindoprilat absorption rates have decreased by 18% and 14%, respectively, versus fasting. No effect of food on the extent of unmetabolized perindopril absorption has been observed.

MANAGEMENT: It is recommended that patients who are taking ACE inhibitors be advised to avoid moderately high or high potassium dietary intake. Particular attention should be paid to the potassium content of salt substitutes. Some authorities recommend administering perindopril before a meal, preferably in the morning. According to the prescribing information, the combination product containing perindopril and amlodipine may be taken with or without food.

Using dilTIAZem together with multivitamin with minerals can decrease the effects of dilTIAZem. Talk with your doctor before using dilTIAZem and multivitamin with minerals together. You may need a dose adjustment or need your blood pressure checked more often if you take both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.