Hi Using ciprofloxacin together with levothyroxine can decrease the effects of levothyroxine. You should separate administration of ciprofloxacin and levothyroxine by several hours to minimize any effect this could have.Oral ciprofloxacin may interact with levothyroxine if they are given together. The most plausible explanation is that ciprofloxacin decreases the absorption of levothyroxine. Antacids, laxatives, colestipol, colestyramine, ferrous sulphate, sulcralfate, and raloxifene have been reported to decrease the absorption of levothyroxine, all quinolones should be used with caution. Blood glucose should be monitored closely whenever quinolones are prescribed to patients receiving oral antidiabetic agents and/or insulin, especially if they are elderly or have renal impairment. Patients should be counseled to recognize symptoms of hypoglycemia such as headache, dizziness, drowsiness, nausea, tremor, weakness, hunger, excessive perspiration, and palpitations. If hypo- or hyperglycemia occur during quinolone therapyTHere is no adverse interactions between cipro and zantac, and they can be safely taken together and interaction between cipro and Elavil is not relevant if taken seperately. So discuss it with your doctor and meanwhile take medicines seperately