Medications in the class of vasodilators include:
- Hydralazine (Apresoline®, Apo-Hydralazine®, Novo-Hylazin®)
Medications in the class of nitrates include:
- Isosorbide Dinitrate (Isordil®, Apo-ISDN®, Coradur®, Novo-Sorbide®)
- Nitroglycerin Patch (Nitro-Dur®, Transderm-Nitro®)
How do these medications work?:
Hydralazine and nitrates are used together to improve the symptoms of heart failure and help you live longer. These medications are often prescribed for those who cannot take an ACEI or ARB. In Black Canadians who have heart failure, they may be used with an ACEI.
Action of Vasodilators and Nitrates:
- Hydralazine is a ‘vasodilator’ and relaxes arteries, allowing blood to flow more easily.
- Nitrates work by relaxing veins.
- Nitrates are available in either an oral tablet or can be in the form of a patch that is placed on the skin.
- These medications both increase the supply of blood and oxygen to the heart and reduce the work of the heart.
How these medications should be taken:
- Take these medications at the same time(s) each day.
- Hydralazine
- Hydralazine is a tablet that is taken three times each day (i.e. every 8 hours). For people with kidney problems, it may be prescribed twice per day (i.e. every 12 hours).
- Hydralazine should be taken at least 1 hour before or 2 hours after a meal.
- Oral nitrate
- Oral nitrate (Isosorbide Dinitrate) is a tablet taken three times each day.
- Nitroglycerin patch
- A nitroglycerin patch is applied in the morning (or night), and is worn for a 12 hour period. After wearing it for 12 hours, the patch is removed to provide a ‘nitrate-free’ period each day. This is so your body does not get used to the medication.
- If you are using a nitroglycerin patch, apply it to a clean, dry area of your body that does not have a lot of hair (such as the shoulder or upper arm). Do not apply the patch to broken, scarred or calloused skin. You can shower with the patch on.
- To prevent a skin reaction apply the patch to a different area each day.
Side effects of vasodilators (hydralazine) may include:
- Headache
- A flushed face (feels warm and looks red)
- Feeling dizzy
- Loss of appetite
- Nausea, vomiting
- Diarrhea or constipation
- Stuffy nose or watery eyes
Serious side effects of vasodilators (hydralazine) include:
- pain or swelling in the joints or muscles
- unexplained fever, chills or a sore throat
- rash, itching or blistering of the skin
- chest pain
- worsening shortness of breath
- fast or irregular heart beat
- fainting
- belly pain
- numbness, tingling, pain or weakness in the hands or feet
Side effects of nitrates may include:
- Headache
- Feeling dizzy
- Skin rash if using a topical patch
- Flushing of the face and neck
What should I remember while taking this medication?
- These medications should be taken at the same time each day.
- Tell your health care provider or pharmacist of any prescription and non-prescription medications you are taking, including vitamins and herbal supplements.
- To prevent feeling dizzy, stand up slowly when sitting or lying down.
- If you develop a headache you can take Tylenol. Do not take non-steroidal anti-inflammatory drugs (NSAIDs). Examples of NSAIDs include: ibuprofen (Advil®, Motrin®), naproxen sodium (Aleve®).
- If you develop a severe headache or a headache that does not get better, talk to your health care provider right away.
- Do not take sildenafil (Viagra®), tadalafil (Cialis®) or Vardenafil (Levitra®) with nitroglycerin as this can cause a dangerous decrease in blood pressure.
- Some side effects may go away as your body gets used to the medication. However, if you develop any of the serious side effects listed above for vasodilators (hydralazine) contact your health care provider right away.
- If you are pregnant, planning on getting pregnant or breastfeeding, talk to your health care provider.
What should I do if I miss a dose?
- Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the dose you missed. Take the next dose at the regular time. Do not take 2 doses at the same time. If you are unsure of what to do, speak to your health care provider or pharmacist.
- Apply the patch as soon as you remember and then take it off at the regular time.
- If you are unsure of what to do, talk with your health care provider or pharmacist.