Methenamine/sodium salicylate, sold under the brand name Cystex among others, is a

combination drug A combination drug is a combination of two or more pharmaceutical drugs as active ingredients combined into a single dosage form, typically as a ''fixed-dose combination'', with each constituent standardized to specifications of a fixed dose. Fix ...

comprising

methenamine Methenamine, also known as hexamine or hexamethylenetetramine and sold under the brand names Hiprex, Urex, and Urotropin among others, is a urinary tract antiseptic and antibacterial medication which is used in the prevention of recurrent urin ...

and

sodium salicylate Sodium salicylate is a sodium salt of salicylic acid. It can be prepared from sodium phenolate and carbon dioxide under higher temperature and pressure. Historically, it has been synthesized by refluxing methyl salicylate (wintergreen oil) with ...

. Methenamine serves as a

urinary The human urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressu ...

antiseptic An antiseptic ( and ) is an antimicrobial substance or compound that is applied to living tissue to reduce the possibility of sepsis, infection, or putrefaction. Antiseptics are generally distinguished from ''antibiotics'' by the latter's abil ...

and

antibacterial agent An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...

, while sodium salicylate is a

nonsteroidal anti-inflammatory drug Non-steroidal anti-inflammatory drugs (NSAID) are members of a Indication (medicine), therapeutic drug class which Analgesic, reduces pain, Anti-inflammatory, decreases inflammation, Antipyretic, decreases fever, and Antithrombotic, prevents bl ...

(NSAID) and

analgesic An analgesic drug, also called simply an analgesic, antalgic, pain reliever, or painkiller, is any member of the group of drugs used for pain management. Analgesics are conceptually distinct from anesthetics, which temporarily reduce, and in s ...

. The combination is used for the treatment and prevention of

urinary tract infection A urinary tract infection (UTI) is an infection that affects a part of the urinary tract. Lower urinary tract infections may involve the bladder (cystitis) or urethra (urethritis) while upper urinary tract infections affect the kidney (pyel ...

(UTI)

symptom Signs and symptoms are diagnostic indications of an illness, injury, or condition. Signs are objective and externally observable; symptoms are a person's reported subjective experiences. A sign for example may be a higher or lower temperature ...

Medical uses

Methenamine, whether used alone or in combination with sodium salicylate, is considered an alternative to

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy ...

s for the treatment and prevention of UTIs and related symptoms. Unlike antibiotics, methenamine does not contribute to the risk of

bacterial resistance Antimicrobial resistance (AMR or AR) occurs when microbes evolve mechanisms that protect them from antimicrobials, which are drugs used to treat infections. This resistance affects all classes of microbes, including bacteria (antibiotic resista ...

Available forms

The drug is available

over-the-counter Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs, which may be supplied only to consumers possessing a valid pres ...

(OTC), including in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

, and is typically taken

by mouth Oral administration is a route of administration whereby a substance is taken through the Human mouth, mouth, swallowed, and then processed via the digestive system. This is a common route of administration for many medications. Oral administ ...

three times per day. Methenamine/sodium salicylate is marketed under several brand names, including ''Cystex Urinary Pain Relief'', ''AZO Urinary Tract Defense'', ''Uro-Pain Dual Action'', and ''CVS Antibacterial Plus Urinary Pain Relief''. Some formulations also include

phenazopyridine Phenazopyridine is a medication which, when excreted by the kidneys into the urine, has a local analgesic effect on the urinary tract. It is often used to help with the pain, irritation, or urgency caused by urinary tract infections, surger ...

and are marketed as products like the ''All-In-One UTI Emergency Kit''.

Comparison with methenamine

Methenamine is also available as a

prescription drug A prescription drug (also prescription medication, prescription medicine or prescription-only medication) is a pharmaceutical drug that is permitted to be dispensed only to those with a medical prescription. In contrast, over-the-counter drugs c ...

and is used alone to prevent recurrent UTIs. Clinical evidence supports its efficacy for this indication. Prescription methenamine is usually administered as the

hippuric acid Hippuric acid (Greek language, Gr. ''hippos'', horse, ''ouron'', urine) is a carboxylic acid and organic compound. It is found in urine and is formed from the combination of benzoic acid and glycine. Levels of hippuric acid rise with the consumpt ...

mandelic acid Mandelic acid is an aromatic alpha hydroxy acid with the molecular formula C6H5CH(OH)CO2H. It is a white crystalline solid that is soluble in water and polar organic solvents. It is a useful precursor to various drugs. The molecule is chiral. The ...

salt In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as r ...

, while the OTC methenamine/sodium salicylate formulation uses methenamine as the

free base In chemistry, a free base (freebase, free-base) is a term for the neutral form of an amine or other Lewis base. The term is used in the pharmaceutical industry in contrast to salt-based formulations like hydrochlorides. The amine is often an ...

. Compared to prescription methenamine, the OTC combination formulation contains lower doses of methenamine. This OTC version has been studied less extensively, and limited clinical data are available to guide its use.

References

{{Portal bar , Medicine Combination drugs Analgesics Antimicrobials Antiseptics Bactericides Nonsteroidal anti-inflammatory drugs Prodrugs

Medical uses

Available forms

Comparison with methenamine

See also

References