Hi. thanks for asking in Healthcare Magic. The antibiotic Ciprofloxacin is very effective against organisms causing urinary tract infections (UTI). It has wide spectrum of activity (effective against many bacteria). It has bactericidal activity (kills bacteria). It is cost effective ie., low cost and greater action. The dose of Ciprofloxacin in UTI is 250 mg twice a day for 3 to 5 days. You are taking a higher dose. Ciprofloxacin can cause anxiety, dizziness, restlessness, impairment of concentration and inability to sleep. It also results in bad taste, swelling of lips and loss of appetite. Ciprofloxacin is an enzyme inhibitor. It reduces the metabolism (destruction) of other drugs given along with it, thereby increasing their blood level. This will increase the side effects of drugs given along with Ciprofloxacin. Anti hypertensive drugs like Prazosin, Clonidine and Alpha methyl Dopa can cause dry mouth. ACE inhibitors like Captopril can cause disgeusia (alteration of taste sensation), swelling of lips, headache and dizziness. Although these side effects are minimal with other ACE inhibitors like Enalapril, when taken along with Ciprofloxacin, these side effects may be more prominent as Ciprofloxacin increases the blood level of these drugs. The side effects you are having can either be due to Ciprofloxacin itself or due to the anti hypertensive (pressure pill) you are taking, occuring due to the enzyme inhibitory action of Ciprofloxacin. I hope this is useful to you.