Patient information: uses, side effects, how to take - Mercaptopurine
What is Mercaptopurine Oral Suspension?
Mercaptopurine Oral Suspension is a prescription medicine used along with other medicines to treat people with acute lymphoblastic leukemia (ALL).
What should I tell my healthcare provider before taking Mercaptopurine Oral Suspension?
Before you take Mercaptopurine Oral Suspension, tell your healthcare provider about all of your medical conditions, including if you:
- have kidney or liver problems.
- have a condition where your body produces too little of the enzyme thiopurine methyltransferase (TPMT) or the enzyme nucleotide diphosphatase (NUDT15).
- have phenylketonuria (PKU). Mercaptopurine contains phenylalanine which is a part of aspartame.
- have recently received or plan to receive a vaccine.
are pregnant or plan to become pregnant. Mercaptopurine Oral Suspension can harm your unborn baby.
If you are a female who is able to become pregnant:
- Your healthcare provider will do a pregnancy test before you start treatment with Mercaptopurine Oral Suspension.
- Use an effective method of birth control (contraception) during treatment with Mercaptopurine Oral Suspension and for 6 months after your last dose. Talk with your healthcare provider about birth control methods you can use during this time.
- Tell your healthcare provider right away if you become pregnant or think you are pregnant during treatment with Mercaptopurine Oral Suspension.
- If you are a male with a female partner who is able to become pregnant:
- Use effective birth control (contraception) during treatment with Mercaptopurine Oral Suspension and for 3 months after your last dose.
- Tell your healthcare provider right away if your female partner becomes pregnant or thinks she is pregnant during your treatment with Mercaptopurine Oral Suspension.
- are breastfeeding or plan to breastfeed. Do not breastfeed during treatment with Mercaptopurine Oral Suspension and for at least 1 week after your last dose.
Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
How should I take Mercaptopurine Oral Suspension?
- See the detailed “Instructions for Use” that comes with Mercaptopurine Oral Suspension for information about the right way to measure and take a dose of Mercaptopurine Oral Suspension.
- Take Mercaptopurine Oral Suspension exactly as your healthcare provider tells you. Do not stop taking Mercaptopurine Oral Suspension or change your dose without talking to your healthcare provider.
- Take Mercaptopurine Oral Suspension by mouth 1 time each day.
- If Mercaptopurine Oral Suspension comes into contact with skin, eyes, or clothes?
- Remove contaminated clothing.
- Wash skin or eyes immediately with water.
- Contact with skin or eyes can cause hypersensitive reactions resulting in rash, redness, itching and inflammation. If symptoms appear seek medical attention.
- During treatment with Mercaptopurine Oral Suspension, your healthcare provider will do blood tests regularly to check your blood cell counts and liver function. Your healthcare provider may change your dose if you have side effects.
- If you miss a dose of Mercaptopurine Oral Suspension, call your healthcare provider for advice.
- If you take too much Mercaptopurine Oral Suspension, call your healthcare provider or go to the nearest emergency room right away.
What should I avoid while taking Mercaptopurine Oral Suspension?
Mercaptopurine Oral Suspension can make your skin more sensitive to sunlight. Protect yourself from sunlight during treatment with Mercaptopurine Oral Suspension.
What are the possible side effects of Mercaptopurine Oral Suspension?
Mercaptopurine Oral Suspension can cause serious side effects, including:
- Decreased blood cell counts are common with Mercaptopurine Oral Suspension but can also be severe. Mercaptopurine Oral Suspension affects your bone marrow and can cause decreased white blood cells, red blood cells, and platelets. Decreased blood cell counts can make you more likely to develop infections, bleeding, or anemia. If you take certain medicines during treatment with Mercaptopurine Oral Suspension, it could make the effects on your bone marrow worse. Tell your healthcare provider if you develop any of the following symptoms during treatment with Mercaptopurine Oral Suspension:
- fever
- sore throat
- cuts or wounds that are red, or swollen, or are draining
- any bleeding
- tiredness or weakness
- shortness of breath
- Liver problems. Increases in liver function test results are common with Mercaptopurine Oral Suspension, but you can also develop severe liver problems with Mercaptopurine Oral Suspension that can lead to death. Your healthcare provider may tell you to stop taking Mercaptopurine Oral Suspension if you develop liver problems. Tell your healthcare provider right away if you develop any of the following symptoms of a liver problem during treatment with Mercaptopurine Oral Suspension:
- decreased appetite
- diarrhea
- nausea or vomiting
- yellowing of your skin or the whites of your eyes
- a build-up of fluid in your stomach-area (ascites)
- Possible increased risk of other cancers. Talk with your healthcare provider about your risk of other cancers if you take Mercaptopurine Oral Suspension.
- Less common side effects of Mercaptopurine Oral Suspension include: loss of appetite, nausea, vomiting, diarrhea, generally do not feel well, and rash.
Low blood sugar (hypoglycemia) can happen, especially in children under six years of age.
Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of Mercaptopurine Oral Suspension.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
How should I store Mercaptopurine Oral Suspension?
- Mercaptopurine Oral Suspension comes in a bottle with a child-resistant cap.
- Store Mercaptopurine Oral Suspension at 20º to 25ºC (68º to 77ºF) [see USP Controlled Room Temperature]. Store in a dry place. Do not store above 25°C.
- Store the oral dispensing syringe in a clean place, with the medicine.
- Mercaptopurine Oral Suspension should be used within 8 weeks after opening the bottle. Dispose of (throw away) any unused medicine after 8 weeks.
- Do not use after the expiry date which is stated on the carton and the bottle after ‘EXP’.
- Keep the bottle tightly closed to prevent spoilage of the medicine and reduce the risk of accidental spillage.
- Keep Mercaptopurine Oral Suspension out of the reach of children, preferably in a locked cupboard. If a child accidentally takes Mercaptopurine Oral Suspension, it could cause death.
How should I dispose of Mercaptopurine Oral Suspension?
- This medicine should not be disposed of in wastewater or household waste. Ask your pharmacist how to dispose of (throw away) Mercaptopurine Oral Suspension that is no longer needed.
General information about the safe and effective use of Mercaptopurine Oral Suspension.
Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use Mercaptopurine Oral Suspension for a condition for which it was not prescribed. Do not give Mercaptopurine Oral Suspension to other people, even if they have the same symptoms you have. It could harm them. You can ask your healthcare provider or pharmacist for information about Mercaptopurine Oral Suspension that is written for health professionals.
What are the ingredients in Mercaptopurine Oral Suspension?
Active ingredient: mercaptopurine, USP
Inactive ingredients: aspartame, ethylparaben sodium, hydrochloric acid, methylparaben sodium, potassium sorbate, raspberry juice powder (raspberry juice, rice syrup solids, silicon dioxide), sodium hydroxide, sucrose, water (purified), xanthan gum.
This Patient Information has been approved by the U.S. Food and Drug Administration.
Distributed by:
Hikma Pharmaceuticals USA Inc.
Berkeley Heights, NJ 07922
C50001544/02
Revised July 2026
INSTRUCTIONS FOR USE
INSTRUCTIONS FOR USE
Mercaptopurine
(mer kapʺ toe pureʹ een)
Oral Suspension
20 mg/mL
Read these Instructions for Use before you start taking Mercaptopurine Oral Suspension, and each time you get a refill. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or your treatment.
Important information about measuring Mercaptopurine Oral Suspension
- Always use the oral dispensing syringe provided with your Mercaptopurine Oral Suspension to make sure you measure the right amount.
- You will be provided:
- 1 bottle of Mercaptopurine Oral Suspension
- 1 bottle adapter
- 2 oral dispensing syringes (one 1 mL and one 5 mL)
If you did not receive an oral dispensing syringe with your Mercaptopurine Oral Suspension, ask your pharmacist to give you one.
You will also need disposable gloves.
| Important Information You Need to Know Before Administering Mercaptopurine Oral Suspension: | ||
| 1. | Wash your hands well with soap and water before and after administering a dose. | |
| 2. | Put on disposable gloves before handling Mercaptopurine Oral Suspension. | |
| 3. | Shake the bottle vigorously for at least 30 seconds to make sure that the medicine is well mixed (See Figure A ). |  Figure A |
| 4. | Remove the child-resistant bottle cap (See Figure B). |  Figure B |
| 5. | Push the smaller end of the bottle adapter into the neck of the bottle until it is firmly in place. The bottom edge of the adapter should fully contact the top rim of the bottle (See Figure C). Do not remove the adapter from the bottle after it is inserted. |  Figure C |
| Preparing a dose of Mercaptopurine Oral Suspension: | ||
| 6. | Hold the bottle upright. Remove the bottle cap by turning in the direction of the arrow (See Figure B). | |
| 7. | Push the tip of the oral dispensing syringe into the hole in the bottle adapter (See Figure D and Figure E). |  Figure D  Figure E |
| 8. | Turn the bottle upside down (See Figure F). |  Figure F |
| 9. | Pull back slowly on the plunger of the oral dispensing syringe to withdraw the prescribed dose of Mercaptopurine Oral Suspension. Pull the plunger back to the mL mark on the syringe that corresponds to the dose prescribed (Figure F). If you are not sure about how much medicine to draw into the oral dispensing syringe, always ask your doctor, pharmacist or nurse for advice. | |
| 10. | Leave the oral dispensing syringe in the bottle adapter and turn the bottle right-side up. Place the bottle onto a flat surface. Hold the oral dispensing syringe by the barrel and carefully remove it from the adapter. Do not hold the oral dispensing syringe by the plunger, because the plunger may come out. | |
| 11. | Place the tip of the oral dispensing syringe in your mouth and aim the tip toward the inside of your cheek. | |
| 12. | Gently squirt the Mercaptopurine Oral Suspension into your mouth by pushing on the plunger until the oral dispensing syringe is empty. Swallow the medicine.
| |
| 13. | Remove the oral dispensing syringe from your mouth. | |
| 14. | Swallow the dose of oral suspension then drink some water, making sure no medicine is left in your mouth. | |
| 15. | Put the cap back on the bottle with the adapter left in place. Close the cap tightly. | |
| 16. | Wash the oral dispensing syringe with warm soapy water and rinse well. Hold the oral dispensing syringe under water and move the plunger up and down several times to make sure the inside of the oral dispensing syringe is clean. Let the oral dispensing syringe dry completely before you use it again for dosing. Do not throw away the oral dispensing syringe after use. | |
Ingredients in Mercaptopurine Oral Suspension
Active ingredient: mercaptopurine, USP
Inactive ingredients: aspartame, ethylparaben sodium, hydrochloric acid, methylparaben sodium, potassium sorbate, raspberry juice powder (raspberry juice, rice syrup solids, silicon dioxide), sodium hydroxide, sucrose, water (purified), xanthan gum.
Storing Mercaptopurine Oral Suspension
- Store Mercaptopurine Oral Suspension at 20º to 25ºC (68º to 77ºF) [see USP Controlled Room Temperature]. Store in a dry place. Do not store above 25°C.
- Store the oral dispensing syringe in a clean place, with the medicine.
- Mercaptopurine Oral Suspension should be used within 8 weeks after opening the bottle. Dispose of (throw away) any unused medicine after 8 weeks.
- Do not use after the expiry date which is stated on the carton and the bottle after ‘EXP’.
- Keep the bottle tightly closed to prevent spoilage of the medicine and reduce the risk of accidental spillage.
- Keep Mercaptopurine Oral Suspension and all medicines out of the reach of children, preferably in a locked cupboard. If a child accidentally takes Mercaptopurine Oral Suspension, it could cause death. Ask your pharmacist how to dispose of (throw away) Mercaptopurine Oral Suspension that is no longer needed.
Disposing of Mercaptopurine Oral Suspension
- Ask your pharmacist how to dispose of Mercaptopurine Oral Suspension that is expired or no longer required. Medicines should not be disposed of via wastewater or household waste.
Clean Up Spillage of Mercaptopurine Oral Suspension
Use appropriate personal protective equipment (disposable gloves and eye protection). Mop up and contain spill material in a compatible container. Wash your hands thoroughly afterwards.
Mercaptopurine Oral Suspension Contact with Skin, Eyes, or Clothes
- Remove and launder contaminated clothing.
- Wash skin or eyes immediately with water.
Contact with skin or eyes can cause hypersensitive reactions resulting in rash, redness, itching and inflammation. If symptoms appear, seek medical attention.
This “Instructions for Use” has been approved by the U.S. Food and Drug Administration.
Distributed by:
Hikma Pharmaceuticals USA Inc.
Berkeley Heights, NJ 07922
C50001544/02
Revised July 2026