Hello, I have gone through your query and understand your concern. From your query i understood that You are suffering from Mild Mitral Stenosis and on injection Benzathine Penicillin G and Tablets Metaprolol and Frusemide with Spironolactone. You are given Injection Benzathine Penicillin G prophylactically to prevent infection in heart called Bacterial Endocarditis. And also you also prescribed Tablets Metaprolol and Frusemide with Spironolactone to control blood pressure. Any of the above drugs are not known to cause low hemoglobin. So the cause could be some thing else and it need further work up. Some common causes are Poor Nutritious diet, Blood loss, Malabsorbtion and Chronic diseases. To identify the exact cause, You need to give detailed history as well as thorough physical examination and further investigations like Stool test for occult blood, Complete blood count and other blood parameters, X-ray chest to rule out any Tuberculosis, Vitamin B12 and folate level, etc.. If the hemoglobin deficient is mild to moderate, then dietary changes are sufficient. You should take iron rich foods like dark-green leafy vegetables, such as watercress and curly kale, iron-fortified cereals, whole grains, such as brown rice , beans, nuts, meat, apricots etc. Take vitamin C rich foods. Vitamin C helps the body absorb iron. Good sources of vitamin C are vegetables and fruits, especially citrus fruits. Citrus fruits include oranges, grapefruits, tangerines etc. Avoid Coffee, tea, milk ( Contains Calcium) as these may reduce the absorption of iron. If hemoglobin level is very low, then you need Injectable either Intramuscular or Intravenous form of Iron to correct the hemoglobin level as soon as possible. Drink plenty of water. Hope this helps. Please write back for further queries. Wishing you good health.