MERCAPTOPURINE

Brand & Generic Names

Purinethol

6-MP

Basic Information

• Habit forming? No
• Prescription needed? Yes
• Available as generic? No
• Drug class: Antineoplastic, immunosuppressant

Uses

• Treatment for some kinds of cancer.
• Treatment for regional enteritis and ulcerative colitis and other immune disorders.

Dosage & Usage Information

How to take:
Tablet--Swallow with liquid.

When to take:
At the same time each day.

If you forget a dose:
Skip the missed dose. Don't double the next dose.

What drug does:
Inhibits abnormal cell reproduction.

Time lapse before drug works:
May require 6 weeks for maximum effect.

Don't take with:
Any other medicine without consulting your doctor or pharmacist.

Overdose

SYMPTOMS:
Headache, stupor, seizures.

WHAT TO DO:

• Dial 911 (emergency) or O (operator) for an ambulance or medical help. Then give first aid immediately.
• If patient is unconscious and not breathing, give mouth-to- mouth breathing. If there is no heartbeat, use cardiac massage and mouth-to-mouth breathing (CPR). Don't try to make patient vomit. If you can't get help quickly, take patient to nearest emergency facility.
• See EMERGENCY Information.

Possible Adverse Reactions or Side Effects

Life-threatening:

In case of overdose, see Overdose section.

Common:

• Black stools or bloody vomit.
• Mouth sores, sore throat, unusual bleeding or bruising.
• Abdominal pain, nausea, vomiting, weakness, tiredness.

Infrequent:

• Seizures.
• Diarrhea, headache, confusion, blurred vision, shortness of breath, joint pain, blood in urine, jaundice, back pain, appetite loss, feet and leg swelling.
• Cough.
• Acne, boils, hair loss, itchy skin.

Rare:

Fever and chills.

Warnings & Precautions

Don't take if:
You are allergic to any antineoplastic.

Before you start, consult your doctor:

• If you are alcoholic.
• If you have blood, liver or kidney disease.
• If you have colitis or peptic ulcer.
• If you have gout.
• If you have an infection.
• If you plan to become pregnant within 3 months.

Over age 60:
Adverse reactions and side effects may be more frequent and severe than in younger persons.

Pregnancy:
Risk to unborn child outweighs drug benefits. Don't use.

Breast-feeding:
Drug passes into milk. Avoid drug or discontinue nursing.

Infants & children:
Use only under special medical supervision.

Prolonged use:

• Adverse reactions more likely the longer drug is required.
• Talk to your doctor about the need for follow-up medical examinations or laboratory studies to check complete blood counts (white blood cell count, platelet count, red blood cell count, hemoglobin, hematocrit), liver function, kidney function, uric acid.

Skin & sunlight:
No problems expected.

Driving, piloting or hazardous work:
Avoid if you feel dizzy, drowsy or confused. Otherwise, no problems expected.

Discontinuing:
Don't discontinue without doctor's advice until you complete prescribed dose, even though symptoms diminish or disappear. Some side effects may follow discontinuing. Report to doctor blurred vision, convulsions, confusion, persistent headache, chills or fever, bloody urine or stools, back pain, jaundice.

Others:

• Drink more water than usual to cause frequent urination.
• Don't give this medicine to anyone else for any purpose. It is a strong drug that requires close medical supervision.
• Report for frequent medical follow-up and laboratory studies.

Possible Interaction with Other Drugs

GENERIC NAME	COMBINED EFFECT
------------------------	-----------------------
Acetaminophen	Increased likelihood of liver
	toxicity.
Allopurinol	Increased toxic effect of
	mercaptopurine.
Anticoagulants*,	May increase or decrease
oral	anticoagulant effect.
Antineoplastic	Increased effect of
drugs, other*	both (may be desirable) or
	increased toxicity of each.
Chloramphenicol	Increased toxicity of each.
Clozapine	Toxic effect on bone marrow.
Cyclosporine	May increase risk of infection.
Immunosuppresants*,	Increased risk of infections and
other	neoplasms*.
Isoniazid	Increased likelihood of liver
	toxicity.
Lovastatin	Increased heart and kidney damage.
Probenecid	Increased toxic effect of
	mercaptopurine.
Sulfinpyrazone	Increased toxic effect of
	mercaptopurine.
Tiopronin	Increased risk of toxicity to bone
	marrow.
Vaccines, live	Increased risk of toxicity or reduced
or killed	effectiveness of vaccine.

Possible Interaction with Other Substances

INTERACTS WITH	COMBINED EFFECT
---------------	---------------
Alcohol:	May increase chance of intestinal
	bleeding.
Beverages:	No problems expected.
Cocaine:	Increases chance of toxicity.
Foods:	Reduced irritation in stomach.
Marijuana:	No problems expected.
Tobacco:	Increases lung toxicity.