| Anastrozole Pharmacology |
| Anastrozole |
| About Anastrozole |
| Non-steroidal Aromatase Inhibitor, Antineoplastic. |
| Mechanism of Action of Anastrozole |
| This non-steroid aromatase inhibitors prevents the formation of estrogens from androgens by binding to the heme portion of cytochrome P450 unit of aromatase enzyme (which catalyze the formation of estrogens from androgens) reversibly and competitively. This reduces the estrogens level in the body and also growth of tumors associated with it. |
| Pharmacokinets of Anastrozole |
| Absorption- Absorbed rapidly and completely after oral administration Distribution- Widely distributed in the body.40% bound to the plasma proteins Metabolism- Metabolized in the liver to its metabolites by N-dealkylation, hydroxylation and glucoronidation. Triazole, hydroxy anastrozole and glucoronide are its inactive metabolites. Excretion -Excreted via urine (11% as parent drug and 60% as its metabolites) and bile |
| Onset of Action for Anastrozole |
| Below 24hrs |
| Duration of Action for Anastrozole |
| Below 6 hrs |
| Half Life of Anastrozole |
| Its plasma half life is 50 hours. |
| Side Effects of Anastrozole |
| 1. Flu-like symptoms 2. Weakness 3. Headache 4. Flushing 5. Sweating 6. Nausea 7. Vomiting 8. Loss of appetite 9. Constipation 10. Diarrhea 11. Heart burn 12.Weight gain 13. Joint pain 14. Bone pain 15. Muscle pain 16. Mood changes 17. Depression 18. Nervousness 19. Dizziness 20. Vaginal bleeding 21. Cough 22 Burning or tingling feeling 23. Dry mouth 24. Hair thinning 25. Chest pain 26. Sore throat 27. Chills 28. Swollen gland 29. Difficulty, painful and urgent urination 30. Blurred vision 31. Tachycardia 32. Breast pain 33. New lumps or masses in the breast or other parts of the body 34. Blisters on skin 35. Hives 36. Rash 37. Difficulty falling asleep or staying 38. Leucopenia 39. Thrombophlebitis 40. Abnormal liver enzyme values |
| Contra-indications of Anastrozole |
| 1. Hypersensitivity to the drug or its ingredients 2. Premenopausal woman |
| Special Precautions while taking Anastrozole |
| Hepatic failure |
| Pregnancy Related Information |
| Contraindicated |
| Old Age Related Information |
| Use with caution |
| Breast Feeding Related Information |
| Contraindicated |
| Children Related Information |
| Contraindicated |
| Indications for Anastrozole |
| 1. Breast cancer in post menopausal woman with disease progression following tamoxifen therapy 2. Prostate hyperplasia 3. Gynecomastia 4. Hypogonadism |
| Interactions for Anastrozole |
| Oestrogen: diminish its pharmacologic action. Tamoxifene: It decreases plasma concentration of Anastrazole |
| Typical Dosage for Anastrozole |
| Adult- Oral- Advanced breast cancer in post menopausal woman: 1mg/day for 5 years |
| Schedule of Anastrozole |
| H |
| Storage Requirements for Anastrozole |
| Stored in a tightly closed container at room temperature. Protect from light and excessive heat. Keep out of reach of children |
| Effects of Missed Dosage of Anastrozole |
| 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 Anastrozole |
| Give symptomatic and supportive treatment. Dialysis and induce vomiting if needed. Monitor patient vital signs closely. |