Mercaptopurine Pharmacology


About Mercaptopurine
Antimetabolite (thiopurine ),immunosuppressent, Antineoplastic.
Mechanism of Action of Mercaptopurine
In the body drug is converted into 6- thioinosine-5`-monophosphate. It inhibits the conversion of inosine monophosphate to adenine monophosphate and guanine monophosphate which is an important step in the purine synthesis. This inhibits the DNA & RNA synthesis of cancer cells.
Pharmacokinets of Mercaptopurine
Absorption-Variant and incomplete absorption after oral administration.
Distribution- Widely distributed in the body. It crosses the blood brain barrier .It enters to the cerebrospinal fluid.
Metabolism- Metabolized in the liver to its metabolites. It also undergoes the first pass metabolism.
Excretion- Excreted via urine.
Onset of Action for Mercaptopurine
Duration of Action for Mercaptopurine
Half Life of Mercaptopurine
Side Effects of Mercaptopurine
1. Nausea
2. Vomiting
3. Difficulty in breathing
4. Closing of the throat
5. Bone marrow suppression
6. Bruising or unusual bleeding
7. Tarry stools
8. Fever
9. Chills
10. Congestive heart failure
11. Diarrhea
12. Loss of appetite
13. Facial flushing
14. Darkening of skin and nails
15. Alopecia
16. Red urine
17. Leucopenia
18. Hyperurecemia
19. Pancreatitis
20. Hepatotoxicity
21. Jaundice
22. Thrombocytopenia
Contra-indications of Mercaptopurine
1. Hypersensitivity to the drug
2. Prior resistance to mercaptopurine and thioguanine
Special Precautions while taking Mercaptopurine
1. Recent chemotherapy
2. Recent radiation therapy
3. Decreased platelet count
4. Depressed neutrophil count
5. Renal dysfunction
6. Hepatic impairment
Pregnancy Related Information
Use with caution
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
Use with caution
Indications for Mercaptopurine
1. Acute leukemia
2. Choriocarcinoma
3. Chronic granulocytic leukemia
4. Systemic lupus erythematosus
5. Rheumatoid arthritis
6. Polyneuritis
7. Acute nephritic syndrome
8. Psoriasis arthritis
9. Erythroid aplasia
10. Myelofibrosis
11. Idiopathic hemolytic anemia
12. Macroglobulinaemia
13. Thrombocytopenia
14. Multiple sclerosis
15. Myasthenia gravis
16. Uveitis
17. Ulcerative colitis
Interactions for Mercaptopurine
Allopurinol: Delayed catabolism of mercaptopurine resulting in severe toxicity. Dose of mercaptopurine should be reduced to one third to one quarter of usual dose.
Other myelosuppressive agents: Enhance anti-neoplastic effect of mercaptopurine, dose of mercaptopurine may need to be reduced.
Trimethoprim-sulfamethoxazole: May result in enhanced bone marrow suppression.
Typical Dosage for Mercaptopurine
2.5 mg/kg/day as a single dose.
If there is no response increase the dose up to 5mg/kg/day.
1.5-2.5 mg/kg/day as a maintenance dose.
1.5 - 2.5 mg/kg/day as a maintenance dose.
Schedule of Mercaptopurine
Storage Requirements for Mercaptopurine
Stored at controlled room temperature. Protect from direct light. Keep out of reach of children.
Effects of Missed Dosage of Mercaptopurine
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Mercaptopurine
Give symptomatic and supportive treatment. Induce emesis and transfuse the blood components.

Home Delivery for Mercaptopurine in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including mercaptopurine.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for mercaptopurine and other medicines and health products. Home delivery services for mercaptopurine may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take mercaptopurine only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for mercaptopurine before they complete the sale. You can get this information while placing the order for mercaptopurine with the pharmacy.

Mercaptopurine is a generic medicine name and there are several brands available for it. Some of the brands for mercaptopurine might be better known than mercaptopurine itself. If the pharmacy that's willing to deliver medicines to your home doesn't have mercaptopurine in stock, you can ask for one of the branded alternatives for mercaptopurine.