<s>[INST] Hi,I have a severe kidney infection. I went to the ER, and had two shots, and was sent home with medication. Its been 48 hours since the antibiotics. Over the last 6 days, which is about how long Ive been sick, Ive gained 8 poundls, while eating less. Is this temporary weight gain ? Is it from the kidneys and will it go away ? [/INST] Hi thanks for posting your query on Chat Doctor. During kidney infections, certain metabolic changes take place which lead to excessive fluid retention by the kidneys. This can cause rapid changes in weight. I strongly recommend you to take diet low in salt as well frequent monitoring of your blood pressure and weight. In case of normal blood pressure, a low dose diuretic like HY Chat Doctor. Consult an expert Nephrologist for further assistance. Thank you, Take care </s>