Hello Thanks for the query to H.C.M. Forum. Since you were already a patient of Rheumatoid arthritis and lupus i.e. prone to hyper acidity & gastritis. You took tamiflu and cephalaxin ( keflex ) as these both drugs produced hyper acidity . The tension of diseases also produced hyperacidity . All these factors as above mentioned develop hyper acidity . Hyper acidity develop nausea , vomiting , loss of appetite . All these causes loss of weight . I would like to advise you following steps for improvement . 1 Try raising the head of your bed about 4 inches with blocks.It might also help to avoid eating or drinking for 2 hours before you lie down.To help control stomach acid one should not drink alcohol or drinks with caffeine in them or eat chocolate or spicy or greasy foods.Also take some antacid but if symptoms are severe then you may need drugs like proton pump inhibitors . 2 Usually in such type of cases I prescribe rebamipide 2-2-2 for 3 months without side effects. 3 Very small amount of milk many times in day will be helpful. Hope these measures will be helpful . Good luck. Dr.HET