Isradipine (Oral)

Isradipine treats hypertension (high blood pressure) by reducing the workload for the blood vessels of the heart.


Isradipine is a drug prescribed to treat high blood pressure. This medication can be used by itself or in combination with other medications (hydrochlorothiazide, for instance) for the treatment of hypertension (high blood pressure). Hypertension contributes negatively to the workload of the arteries and heart. If these issues are prolonged and continue for a long duration, the arteries and heart may begin to improperly function. This can result in damage to the kidneys, heart, and brain blood vessels; and this can cause kidney failure, heart failure, or stroke. Hypertension can also increase the likelihood of heart attacks taking place. These issues could be less likely to take place if blood pressure is monitored and regulated.

Isradipine impacts the way calcium moves through the cells of the blood vessels and heart; it is a calcium channel blocker medication. Isradipine helps the blood vessels to relax, lowers the workload for the heart, and maximizes the amount of oxygen and blood that are moving to the heart.

Isradipine can only be obtained with a valid prescription from your physician. It is currently available in capsule, tablet, and tablet (extended release) forms. Isradipine is manufactured under the US brand names Dynacirc and Dynacirc CR.

Condition treated

  • Hypertension (high blood pressure)

Type of medicine

  • Calcium channel blocker

Side Effects

In addition to the benefits this medication may provide, almost any medication can cause undesired side effects. While it is not typical for every side effect to take place, if they do they could require medical care.

Consult with your physician right away if you experience any of the side effects below while taking isradipine.

More Common Side Effects (Medical Care Required)

  • Tingling of the feet or hands
  • Weight loss or gain (unusual)
  • Swelling or bloating of the feet, lower legs, hands, arms, or face

Less Common Side Effects (Medical Care Required)

  • Wheezing
  • Weakness or tiredness (unusual)
  • Vomiting
  • Swelling of stomach or abdominal area
  • Stomach pressure
  • Sensations of warmth
  • Redness of the upper chest, arms, face, or neck
  • Pulse racing, pounding, irregularity, or quickness
  • Nausea
  • Heartbeat racing, pounding, irregularity, or quickness
  • Dizziness
  • Chest tightness
  • Chest pain
  • Breathing difficulty
  • Breath shortness
  • Bloated or full feeling

Seek emergency medical treatment right away if you experience any of the symptoms of overdose below:

Symptoms of Overdose

  • Vision blurred
  • Sweating
  • Lightheadedness, faintness, or dizziness when standing suddenly from a sitting or lying position
  • Flushing
  • Confusion

Sometimes, side effects can take place but these do not typically require medical care. These side effects may disappear throughout the course of treatment as you become more adjusted to isradipine. In addition, your physician can inform you of additional methods of preventing or reducing certain side effects. Consult with your physician if the side effects below become prolonged, bothersome, or if you have concerns or questions regarding them.

More Common Side Effects (Medical Care Not Required)

Less Common Side Effects (Medical Care Not Required)

  • Stomach discomfort or soreness
  • Rash
  • Difficulty passing a stool (bowel movement)
  • Diarrhea

Some patients may experience additional side effects. If you observe or experience any other side effects, consult with your physician.

Contact your doctor if you need medical advice regarding any side effect. The FDA also takes reports of side effects, and they can be reached by calling 1-800-FDA-1088.


Blood pressure treatment could include this medication, weight control, and possibly adjustments to your diet (specifically high-sodium foods). Your physician will be able to inform you about which foods are going to be the most important for your case. Be sure to ask your doctor prior to adjusting your diet.

Many individuals with higher levels of blood pressure may not realize they have outward symptoms of the issue. Actually, a lot of patients may feel like they normally do. It is highly imperative that you take isradipine precisely as instructed and that you make it to every checkup with your physician, even if you are feeling fell.

This medication cannot cure high blood pressure, however it is helpful for controlling it. You should take this medication as prescribed if you want to maintain low levels of blood pressure. You may need to be on high blood pressure medication for the remainder of your life. High blood pressure left untreated can cause serious health issues, specifically kidney disease, stroke, blood vessel disease, or heart failure.

Never chew, crush, or break isradipine tablets. Take the entire tablet with water.

Patients who are taking the tablets that are extended-release may find out that a portion of the tablet could end up in your stool after the medication is completely absorbed by your body. Do not worry about this; it is usual.

Different patients will be given a unique dose of isradipine based on their specific medical needs. Be sure to follow the instructions given by your physician or the medication label instructions. The data listed below summarizes only general doses of isradipine. If you were given a dose that differs from the following information, do not adjust it unless instructed by your physician.

The quantity of medication taken will depend on how strong the medication is. Also, the total number of doses taken per day, the allotted time between each dose, and the total duration for which you take isradipine depends on your medical issue for which the medication was prescribed.

For treatment of high blood pressure:

For capsule form (oral dose):

  • Adults: Initially, take 2.5 mg (milligrams) twice daily. Your physician may decide to increase how much medication you are taking, as required.
  • Children: The pediatrician must calculate dose and usage information.

For tablet form (extended release, oral dose)

  • Adults: Patients should take 5 mg (milligrams) once per day initially. The physician may adjust dosage information as needed.
  • Children: Use and dose should be determined by pediatrician.

Missed Dose

If a dose of isradipine is accidentally missed, it should be taken as soon as you remember that it was skipped. However, if it is closer to the scheduled next dose, the skipped dose should remain missed and you may just return to the original dosage schedule. Never take a double dose of isradipine.


Drug Interactions

Some drugs should never be taken at the same time, but in certain cases two medications may be used at the same time, even if there is a chance that an interaction could take place. Under these circumstances, your physician may choose to change your dose, or they may decide to take other precautions to protect your unique situation as a patient. While taking isradipine, it is highly important that your doctor is aware if you are taking any of the medications below. The list of interactions below was chosen due to the possible significance of the interaction when taken with isradipine. This list may not be all-inclusive.

Taking isradipine with the medications below is not suggested. Your medical care professional may choose not to prescribe isradipine, or they may alter other medications you may be taking.

  • Mefloquine

Taking this medication with any of the drugs listed below is not typically suggested, but certain extreme situations may require it. Under these circumstances, your physician will likely reduce the dose or frequency for either just one or possibly both drugs.

  • Zolmitriptan
  • Vasopressin
  • Trimipramine
  • Trimethoprim
  • Trimeprazine
  • Triflupromazine
  • Trifluoperazine
  • Thiethylperazine
  • Telithromycin
  • Tedisamil
  • Sulfamethoxazole
  • St John's Wort
  • Spiramycin
  • Sotalol
  • Sematilide
  • Quinidine
  • Protriptyline
  • Propiomazine
  • Propafenone
  • Promethazine
  • Promazine
  • Prochlorperazine
  • Procainamide
  • Probucol
  • Prajmaline
  • Pirmenol
  • Pipotiazine
  • Perphenazine
  • Pentamidine
  • Ondansetron
  • Octreotide
  • Nortriptyline
  • Methotrimeprazine
  • Lorcainide
  • Lidoflazine
  • Lacosamide
  • Isoflurane
  • Imipramine
  • Idelalisib
  • Ibutilide
  • Hydroquinidine
  • Halothane
  • Halofantrine
  • Gemifloxacin
  • Foscarnet
  • Fluphenazine
  • Fluoxetine
  • Fluconazole
  • Flecainide
  • Ethopropazine
  • Erythromycin
  • Enflurane
  • Encainide
  • Droperidol
  • Doxepin
  • Dolasetron
  • Dofetilide
  • Disopyramide
  • Digoxin
  • Dibenzepin
  • Desipramine
  • Dantrolene
  • Clopidogrel
  • Clarithromycin
  • Chlorpromazine
  • Chloroquine
  • Chloral Hydrate
  • Ceritinib
  • Bretylium
  • Azimilide
  • Astemizole
  • Arsenic Trioxide
  • Aprindine
  • Amoxapine
  • Amitriptyline
  • Amiodarone
  • Ajmaline
  • Acetophenazine
  • Acecainide

Taking isradipine with any of the medications below can trigger an increased likelihood of some side effects taking place, however the combination of drugs could be the most optimal form of treatment for your unique conditions. If your physician chooses to prescribe both medications, they may reduce the dose or frequency for either or both medications.

  • Rifampin
  • Quinupristin
  • Magnesium
  • Ketoconazole
  • Indinavir
  • Dalfopristin
  • Amprenavir

Other Interactions

Patients should take caution when taking medications near mealtime. Some medications should not be taken with food, due to the possibility of interactions taking place. The use of tobacco and alcohol can also impact side effects of some medications and may trigger additional interactions. Always consult with your physician regarding how tobacco, food, or alcohol impacts the use of isradipine.

Medical Interactions

Patients who have additional medical issues may experience usefulness in the effectiveness of this medication. Be sure to inform your physician if you experience other types of medical issues, specifically:

  • Liver disease (Take caution; isradipine side effects could be increased due to the slower elimination of the medication from your body)
  • Kidney disease
  • Congestive heart failure (Take caution; conditions may worsen for patients with heart failure)
  • Blockage of the bowels


Your physician must carefully monitor your progress while you are taking isradipine at regular appointments. They must be able to see how the medication is working, and they also need to monitor for undesired side effects.

Hypotension (low blood pressure) could take place while on this medication. Consult with your physician immediately if you experience any of these symptoms:

  • Weakness or tiredness (unusual)
  • Sweating
  • Severe faintness, lightheadedness, or dizziness when standing quickly from a sitting or lying position
  • Confusion
  • Blurred vision

This medication can trigger edema (fluid retention) for certain patients. Inform your physician immediately if you have any of the symptoms below:

  • Unusual weight loss or gain
  • Tingling of feet or hands
  • Swelling or bloating of the feet, lower legs, hands, arms, or face

When attempting to decide whether or not a medication is right for you, please carefully compare the risks of the medication against the benefits it could provide. You must make this choice carefully with your physician. Consider the following points for this medication:


Inform your medical care professional if you are currently or have ever experienced allergic reactions to this medication or other medications. Also inform your medical care professional if you experience other kinds of allergies, for instance to animals, preservatives, dyes, or foods. Be sure to carefully read the ingredients summary on the package label carefully for any product that is non-prescription.

Specific Demographic Use


Current research has not identified how age relates to isradipine's effects for pediatric patients. Effectiveness and safety has not been determined.


Current research has not outlined any issues that are specific to elderly patients that could inhibit the effectiveness of this medication for geriatric patients. However, patients who are elderly have a higher chance of having kidney or liver issues, which could necessitate a dose adjustment for patients who want to take isradipine.


It is unclear whether or not this medication is safe and effective for pregnant women and their babies. Either research in animal patients has revealed a negative effect and similar research has not yet been conducted for women who are pregnant; or, no animal or human research has taken place.


Current research has not identified dangers to the infant that may take place if the mother takes isradipine while breastfeeding. Mothers should compare the possible benefits the medication may provide against the potential dangers prior to taking this medication and breastfeeding.


Isradipine should always be stored in a container that is sealed and kept at room temperature. Be sure to keep the prescription away from moisture, heat, freezing temperatures, and direct sunlight, as exposure to these elements can alter the chemical composition of the medication. Do not keep this medication in a place where children can easily reach it.

Medication that is expired or no longer needed to treat your medical condition should be disposed of. Consult with your physician to find out how to properly dispose of unused medications.


Isradipine treats high blood pressure (hypertension). It can be used by itself or in combination with other medications for the treatment of hypertension. Hypertension adds more of a workload to the arteries and heart. When these issues become prolonged, the arteries and heart may no longer function as they should. This can produce damage to the kidneys, heart, and brain blood vessels; and can cause kidney failure, heart failure, or stroke. Hypertension can also raise the chance of the patient having a heart attack. These problems can be regulated if blood pressure is monitored carefully.

This medication impacts how calcium transfers through the blood vessels and heart, and it belongs to the calcium channel blocker medicine category. Isradipine aids the blood vessels in relaxing, which then lowers the workload for the heart, and also improves how much oxygen and blood are reaching the heart.