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Sildenafil (Pulmonary Arterial Hypertension)

Drug Class: Commonly Known As: Category:
PDE5 inhibitor Viagra

Sildenafil (Pulmonary Arterial Hypertension) - What is it for

​Sildenafil is used to treat high blood pressure in the blood vessels in the lungs (pulmonary arterial hypertension). Sildenafil works by relaxing and widening the blood vessels in the lungs, and ultimately lowering the pressure in the lungs.

This should improve your symptoms such as breathlessness, and increase your ability to exercise. This medication has to be taken on a daily basis.

This medication may also be used for other conditions. Check with your healthcare professional if you are unsure why you are given this medication.

Sildenafil (Pulmonary Arterial Hypertension) - Side Effects, Precautions, and Contraindications

What side effects can Sildenafil (Pulmonary Arterial Hypertension) cause?

  • ​Facial flushing where the skin on your face feels hot
  • Headache
  • Giddiness due to low blood pressure
  • Visual disturbances (including blurring of vision, blue tinge in vision)
  • Indigestion or stomach pain
  • Nosebleed

Priapism (an erection that will not go away) - If you have an erection that lasts more than 4 hours, get medical help right away. If it is not treated right away, priapism can permanently damage your penis.

Sudden vision loss in one or both eyes - Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy (NAION).

Sudden hearing decrease or hearing loss - Some people may also have ringing in their ears (tinnitus) or dizziness.

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

Before taking Sildenafil (Pulmonary Arterial Hypertension), what precautions must I follow?

​Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients of this medication
  • You are taking medicines called Nitrates (such as sublingual nitroglycerin (also known as Glycerin Trinitrate or GTN), Isosorbide Mononitrate or Isosorbide Dinitrate), as the combination may lead to a dangerous fall in your blood pressure. Nitrates must be withheld at least 24 hours after the last dose of Sildenafil or Vardenafil, and 48 hours after the last dose of Tadalafil.

Tell your doctor if you are taking any of these medicines which are often given for relief of angina (chest pain).  If you are not certain, ask your healthcare professional.

  • You are taking medicines called Alpha-1 Blockers (such as Tamsulosin, Terazosin, Prazosin, Alfuzosin), as the combination may further lower your blood pressure. In order to reduce the chances of these symptoms occurring, you should be on a regular daily dose of your Alpha-1 blockers before you start drugs for erectile dysfunction.
  • You recently had a stroke or a heart attack, low blood pressure or uncontrolled high blood pressure
  • You have severe heart, liver or kidney  problem
  • You have certain rare inherited eye diseases (such as retinitis pigmentosa)
  • You have a stomach ulcer or bleeding problem
  • You have sickle cell anaemia (an abnormality of red blood cells)
  • You have a deformity of your penis

Female patients of childbearing age should take precautions to avoid pregnancy by seeking advice from gynaecologist for effective contraceptive methods. If you suspect you may be pregnant, inform your cardiologist as soon as possible.

What food or medicine must I avoid when I take Sildenafil (Pulmonary Arterial Hypertension)?

​Avoid taking grapefruit,or grapefruit juice as they may interact with your medication and increase the risk of side-effects.

Inform your healthcare professional if you are taking or intend to take any other medication, supplements, traditional medications or herbal remedies.

This includes certain medications such as:

  • Antibiotics
  • Anti-fungal medications
  • Medications used to treat human immunodeficiency virus (HIV) infection

Sildenafil (Pulmonary Arterial Hypertension) - Dosage and How to Use

How should Sildenafil (Pulmonary Arterial Hypertension) be used?

  • ​Do not stop taking your medication without checking with your healthcare professional as it may worsen your condition.
  • This medication may be taken with or without food
  • This medication is usually started at a lower dose. Medication dosage will be adjusted based on your condition and your response to this medication will be monitored closely.

What should I do if I miss a dose?

  • ​Take the missed dose as soon as you remember. Skip the dose if it is too near to your next dose. Then take your next dose at the usual time. Do not take two doses to make up for the missed dose.
  • Do not take more than the dose prescribed to you.

What should I do if I overdose?

Sildenafil (Pulmonary Arterial Hypertension) - Handling

How should I handle Sildenafil (Pulmonary Arterial Hypertension) safely?

Sildenafil (Pulmonary Arterial Hypertension) - Storage

How should I store Sildenafil (Pulmonary Arterial Hypertension)?

Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#

How should I dispose of Sildenafil (Pulmonary Arterial Hypertension) safely?

​Pack this medication into a black trash bag and seal it tightly before throwing into the rubbish chute or bin.

Sildenafil (Pulmonary Arterial Hypertension) - Additional Information

  • Updated on Monday, September 30, 2019
  • Article contributed by PSS National Medication Information Workgroup

    The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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