Visqid A/A, or methenamine and sodium phosphate, is a prescription medication. This prescription drug is in the urinary anti-infectives drug class. Visqid A/A is used most often in order to prevent urinary tract infections. Urinary tract infections are very common and if you suspect that you have a urinary tract infection, then you are advised to consult your doctor. Visqid A/A is often prescribed to a patient after his or her first urinary infection to prevent many more urinary infection from occurring. Visqid A/A is administered most commonly by mouth. The dosage of this prescription medication can be adjusted by your doctor in order to get the proper amount of Visqid A/A. Always consult your doctor for adjustments to your medication.