Thelin: Uses, Side Effects and Dosage

ABOUT THIS MEDICATION

What this medication is used for:

THELIN has been prescribed to treat your symptoms of pulmonary arterial hypertension (high blood pressure in the blood vessels leading to the lungs)

THELIN is used for the treatment of:

1. 1.

   Idiopathic (meaning the cause is not known) pulmonary

   arterial hypertension (IPAH), also known as primary pulmonary hypertension;

2. 2.

   Pulmonary arterial hypertension resulting from connective

   tissue disease (such as arthritis), in patients with specific other symptoms identified and diagnosed by your doctor.

THELIN is only available on prescription. This medicine should be used exactly as recommended by your doctor. Do not change the dose or any part of your treatment without your doctor’s advice.

What it does:

THELIN lowers blood pressure by widening the blood vessels leading to the lungs, so your heart can pump blood more effectively. You should know that THELIN is working because you should experience a gradual increase in your ability to tolerate more activity than you could do before starting THELIN.

When it should not be used:

Do not use THELIN if:

• you are pregnant, are thinking of becoming pregnant, or could get

  pregnant because you are not using reliable birth control methods

• you are breastfeeding

• you are taking cyclosporine (a drug which may be taken to prevent

  rejection following an organ transplant or for psoriasis or rheumatoid arthritis)

• you are allergic to sitaxsentan sodium or if you are allergic to any

  of the ingredients in THELIN tablets (see What the important nonmedicinal ingredients are)

• you have suffered any prior liver disease or impairment
• THELIN is not recommended for children

What the medicinal ingredient is:

Sitaxsentan sodium

What the important nonmedicinal ingredients are:

anatose titanium dioxide, ascorbyl palmitate, dibasic sodium phosphate, edetate disodium dihydrate, hydroxypropyl methylcellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, monobasic sodium phosphate, pharmaceutical talc, sodium starch glycolate, stearic acid, and yellow iron oxide dehydrate.

What dosage forms it comes in:

Tablets 100 mg.

WARNINGS AND PRECAUTIONS

Serious Warnings and Precautions

THELIN has been associated with liver damage and disease.

BEFORE you use THELIN talk to your doctor or pharmacist:

• if you are pregnant or intend to become pregnant;
• if you are breastfeeding
• if you have had an allergic reaction to THELIN, any of its ingredients (see What the important nonmedicinal ingredients are) or if you have had an allergic reaction to any similar treatment, such as bosentan (another drug used for PAH)
• if you suffer from liver problems or if you notice any of the following symptoms which may indicate liver problems: upset stomach (nausea), vomiting, loss of appetite, fever, unusual tiredness, pain in your stomach area (abdomen) or yellowing of the skin or of the whites of your eyes (jaundice) Tests Required During Treatment

Some patients taking THELIN were found to have abnormal liver function values (increase in liver enzymes) and some patients developed anemia (reduction in red blood cells). Because these findings may not cause symptoms you can feel or observe yourself, your doctor will do regular blood tests to assess any changes in your liver function and hemoglobin level.

The effects on a human fetus exposed to THELIN in the womb are not known but it is likely that THELIN will produce major birth defects if used by pregnant women. Therefore, pregnancy must be ruled out before starting treatment on THELIN and then prevented using a reliable method of birth control. Monthly pregnancy tests are recommended.

Test Results

If you develop abnormal liver function, your doctor may decide to stop treatment with THELIN. When your blood test results for liver function return to normal, your doctor may decide to restart treatment with THELIN. If you develop anemia, your doctor may decide to perform further tests to investigate the cause.

If there is any delay in onset of your period (for females) or any other reason to suspect pregnancy, you must notify your doctor immediately for a pregnancy test. If the pregnancy test is positive, discuss the risk to the fetus with your doctor.

Your regular tests are an important part of your treatment. We suggest you keep a diary of your most recent and upcoming tests. Ask your doctor when each test is due.

IMPORTANT PLEASE READ

^PrTHELIN^® (sitaxsentan sodium tablets) Product Monograph Page 28 of 28

INTERACTIONS WITH THIS MEDICATION

Drugs that may interact with THELIN include:

1. 1. Warfarin (a blood thinning agent)
2. 2. Cyclosporine (DO NOT USE With THELIN)
3. 3. Phenytoin (Dilantin), to control epilepsy/seizures

PROPER USE OF THIS MEDICATION

Usual Dose:

The usual dose of THELIN in adults is 1 tablet (100 mg) per day, taken by mouth with or without food, without regard to the time of day.

Doses above 100 mg once daily are not recommended.

Overdose:

In the event of an overdose, either see a doctor or go to a hospital immediately.

Missed Dose:

If you forget a dose, take it as soon as you remember it. If it is almost time for your next dose, skip the one you missed. Do not take two doses to make up for a missed dose

Never change the dose of THELIN without instructions from your doctor.

SIDE EFFECTS AND WHAT TO DO ABOUT THEM

In addition to its intended action, any medicine may cause side effects. Tell your doctor if you feel in any way unwell or experience unusual side effects while taking THELIN.

Some common side effects may include headache, upset stomach, constipation, swelling of the hands or feet, nasal congestion, nose bleed, flushing, muscle cramps, and insomnia.

Less common side effects include:

Ears: ringing, wax blockage or infections.

Eye: irritations, infections, red, watery.

Mouth: sore, dry, bleeding.

More prone to viruses, yeast and fungal infections.

Higher or lower blood sugar levels.

Although symptoms of liver problems are rare with THELIN, talk to your doctor right away if you start having: persistent upset stomach (nausea), vomiting, loss of appetite, fever, unusual tiredness, pain in your stomach area (abdomen), or yellowing of the skin or whites of your eyes (jaundice).

This is not a complete list of side effects. If you experience any unexpected symptoms while taking THELIN, contact your doctor or pharmacist.

HOW TO STORE IT

Store at room temperature (15ºC –25ºC). Protect from heat and moisture.

Keep in a safe place out of the reach of children.

REPORTING SUSPECTED SIDE EFFECTS

To monitor drug safety, Health Canada collects information on serious and unexpected effects of drugs . If you suspect you have had a serious or unexpected reaction to this drug you may notify Health Canada by:

toll-free telephone: 866-234-2345 toll-free fax 866-678-6789

By email: cadrmp@hc-sc.gc.ca

By regular mail:

National AR Centre

Marketed Health Products Safety and Effectiveness Information Division

Marketed Health Products Directorate

Tunney’s Pasture, AL 0701C

Ottawa ON K1A 0K9

NOTE: Before contacting Health Canada, you should contact your physician or pharmacist.

MORE INFORMATION

This document plus the full product monograph, prepared for health professionals can be found by contacting the sponsor, Pfizer Canada Inc., at:

Pfizer Canada Inc.

17 300 Trans-Canada Highway

Kirkland, Quebec H9J 2M5

Medical Information 1800 463 6001

Safety reporting Fax 1-877-526-7233 http://www.Pfizer.ca 1-877-684-3546

Last revised: April 26, 2010