PrescriptionGiant is a FREE prescription savings program that can save you up to 75% on your prescriptions with or without insurance!

Isordil (Generic Isosorbide)

Actual product appearance may differ slightly.

Click the CARD below to print or take a screenshot on your mobile phone or tablet. There is no need to download another app!


If you would like to personalize your card enter your full name in the member name field below the card at this link and click the Update button.

Why is this medication prescribed?

Isosorbide is prescribed for the treatment of angina pectoris, a condition characterized by chest pain or discomfort due to reduced blood flow to the heart. It belongs to a class of medications called nitrates, which work by dilating the blood vessels, improving blood flow, and reducing the workload on the heart.

Isosorbide can be used to prevent angina attacks (prophylactic use) or to relieve acute angina episodes (acute use). It is available in different formulations, including immediate-release tablets, extended-release tablets, and oral sprays.

How should this medicine be used?

The specific instructions for using Isosorbide may vary depending on the formulation and the individual’s condition. Therefore, it is crucial to follow the directions provided by the prescribing healthcare professional. However, here are some general guidelines:

  • Immediate-release tablets: These are usually taken two to three times a day, with a gap of at least six hours between doses. The tablets should be swallowed whole with water and not crushed or chewed.
  • Extended-release tablets: These are designed to provide a sustained effect over a longer duration. They are typically taken once daily, with or without food, and should be swallowed whole without crushing or chewing.
  • Oral sprays: Isosorbide dinitrate oral sprays are used to relieve acute angina episodes. The prescribed number of sprays should be administered under the tongue, as directed by the healthcare professional. It is important to avoid inhaling the spray.

It is essential to strictly adhere to the prescribed dosages and schedules for Isosorbide. Do not stop or adjust the medication without consulting a healthcare professional, as sudden discontinuation may lead to rebound angina or other adverse effects. If you have any specific concerns or questions about the use of Isosorbide, it is recommended to consult your doctor or pharmacist for personalized advice.

Other uses for this medicine

Isosorbide has a primary indication for the treatment of angina pectoris, but it may also be used for other medical conditions as determined by a healthcare professional. Some potential off-label uses of Isosorbide include:

  • Heart failure: Isosorbide dinitrate may be used in combination with other medications for the treatment of heart failure, a condition where the heart is unable to pump blood efficiently.
  • Pulmonary hypertension: Isosorbide mononitrate has been used off-label for the treatment of pulmonary hypertension, a condition characterized by high blood pressure in the arteries of the lungs.

It’s important to note that the off-label use of Isosorbide should only be done under the guidance and supervision of a healthcare professional.

What special precautions should I follow?

Regarding precautions, it is essential to follow these recommendations when using Isosorbide:

  • Inform your healthcare provider about any known allergies to Isosorbide or any other medications, as well as any other allergies you may have.
  • Provide a complete medical history to your doctor, especially if you have a history of low blood pressure (hypotension), recent heart attack, heart failure, kidney or liver disease, or anemia.
  • Isosorbide can cause dizziness or lightheadedness, especially when rising from a sitting or lying position. Take caution while performing activities that require mental alertness until you know how the medication affects you.
  • Grapefruit and grapefruit juice may interact with Isosorbide and lead to potentially harmful effects. It is advisable to avoid consuming grapefruit or grapefruit products while taking Isosorbide.
  • Inform your healthcare provider about all other medications, including prescription, over-the-counter drugs, and herbal supplements you are taking, as they may interact with Isosorbide. Certain medications, such as sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra), can cause a severe drop in blood pressure when combined with Isosorbide.
  • If you are pregnant or breastfeeding, consult your healthcare provider before using Isosorbide, as its safety during pregnancy or lactation has not been well established.

It is crucial to adhere to the specific precautions provided by your healthcare professional, as they can consider your individual circumstances and provide tailored advice.

What special dietary instructions should I follow?

When it comes to dietary instructions for isosorbide, there are no specific dietary restrictions you need to follow. However, it’s generally recommended to follow a healthy and balanced diet to support your overall cardiovascular health. This includes consuming a variety of fruits, vegetables, whole grains, lean proteins, and limiting your intake of saturated and trans fats, cholesterol, sodium, and added sugars.

What should I do if I forget a dose?

If you happen to forget a dose of isosorbide, take it as soon as you remember, unless it is close to the time for your next scheduled dose. In that case, skip the missed dose and resume your regular dosing schedule. Do not take a double dose to make up for the missed one.

What side effects can this medication cause?

Isosorbide, like any medication, can potentially cause side effects. Not everyone experiences side effects, and their severity can vary from person to person. It’s important to be aware of possible side effects and discuss any concerns with your healthcare provider. Here are some commonly reported side effects of isosorbide:

  • Headache: This is the most common side effect of isosorbide. It can range from mild to severe and usually goes away with continued use of the medication.
  • Dizziness or lightheadedness: Isosorbide can cause a drop in blood pressure, which may lead to dizziness or lightheadedness. It’s important to get up slowly from a sitting or lying position to minimize the risk of falling.
  • Flushing: Some people may experience a warm, flushed feeling or redness of the skin. This is generally temporary and not a cause for concern.
  • Nausea or vomiting: Isosorbide may cause gastrointestinal symptoms such as nausea or vomiting in some individuals. Taking the medication with food or adjusting the dosage timing can sometimes help alleviate these symptoms.
  • Low blood pressure: Isosorbide’s primary action is to widen blood vessels, which can result in a drop in blood pressure. This can lead to symptoms such as weakness, fatigue, fainting, or feeling lightheaded. It’s important to monitor your blood pressure regularly, especially when starting the medication or adjusting the dosage.
  • Rapid heart rate or palpitations: Some individuals may experience an increased heart rate or palpitations while taking isosorbide. If these symptoms are persistent or concerning, it’s important to consult your healthcare provider.

These are not all possible side effects of isosorbide. If you experience any other unusual or bothersome symptoms while taking the medication, it’s important to notify your healthcare provider for further evaluation.

It’s worth noting that serious side effects are rare, but they can occur. If you experience symptoms such as severe dizziness, fainting, chest pain, or difficulty breathing, seek immediate medical attention.

Always follow your healthcare provider’s instructions regarding the use of isosorbide and report any side effects promptly. They can provide guidance on managing side effects or adjust your treatment plan if needed.

What should I know about storage and disposal of this medication?


  • Keep Isosorbide in its original container or packaging, tightly closed.
  • Store it at room temperature, away from excessive heat, moisture, and direct sunlight.
  • Avoid storing Isosorbide in the bathroom or any area with high humidity.
  • Keep Isosorbide out of reach of children and pets.
  • Do not use Isosorbide past its expiration date. If you have any outdated or unused medication, dispose of it properly.


  • Do not flush Isosorbide down the toilet or pour it down the drain unless specifically instructed to do so.
  • Check if there are any take-back programs or community disposal options available in your area. These programs can safely dispose of unused medications.
  • If there are no specific disposal instructions, mix the Isosorbide with an undesirable substance like dirt, cat litter, or coffee grounds in a sealed plastic bag before throwing it in the regular trash. This helps prevent accidental ingestion by animals or children.

In case of emergency/overdose

  • In case of an emergency, such as a suspected overdose or severe allergic reaction, call your local emergency number immediately.
  • If you are in the United States, you can contact the Poison Control Center at 1-800-222-1222 for guidance.
  • It is important to have the original container or packaging of the medication available to provide relevant information to healthcare professionals in case of an emergency.
  • Do not induce vomiting unless instructed to do so by a medical professional.

What other information should I know?

  • Take Isosorbide exactly as prescribed by your healthcare provider. Do not change the dosage or stop taking it without consulting your doctor.
  • If you miss a dose, take it as soon as you remember. If it is close to the time for your next dose, skip the missed dose and resume your regular dosing schedule.
  • Inform your healthcare provider about any other medications you are taking, as Isosorbide may interact with certain drugs, such as erectile dysfunction medications (e.g., sildenafil, tadalafil).
  • Isosorbide may cause dizziness or lightheadedness, especially when you get up from a lying or sitting position. Be cautious while performing tasks that require mental alertness until you know how the medication affects you.
  • Inform your healthcare provider if you experience any side effects, such as headache, flushing, or low blood pressure.

Remember, this information is not exhaustive, and it’s important to consult your healthcare provider or pharmacist for specific guidance and instructions regarding of Isosorbide.

Copyright © 2023