Methenamine is a Medicine belongs to Antibacterials group whose information about Brand can be referenced from   Book : Martindale    Page : 323   Edition : 38,

  ►   Brandname : Hiprex,Mandelamine,Urex

  ►  Strength : Tablet with 0.5  gm, Tablet with 1  gm, Suspension with 0.5/5  gm/ml, Elixir with   , Oral solution with   , Deodorant with   ,

Reference of this Medicine for its Strength can be taken from   Book : Basic & Clinical pharmacology    Page : 898   Edition : 12, Martindale    Page : 323   Edition : 38,
A Route of administration in pharmacology and toxicology is the path by which a drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance is applied. Common examples include oral and intravenous administration.

  ►  Route of administration : Oral, Topical,
Reference :-   Book : Martindale    Page : 323   Edition : 38,

Dosing of Medicine differ in Adult & Pediatrics ↓


Adult Dose

S.No Ailment   Route   Dose Min   Dose Max   Unit   Dosage Form   Frequency   Additional Info
1 Long term suppression of chronic or recurrent, uncomplicated, lower urinary-tract infections and asymptomatic bacteriuria. Oral 1 gm Tablet q.i.d.
2 Long term suppression of chronic or recurrent, uncomplicated, lower urinary-tract infections and asymptomatic bacteriuria. Oral 1 gm Tablet b.d. For Methenamine hippurate.

Ref :-  Book : Martindale    Page : 323   Edition : 38,




Pediatric Dose

S.No Ailment   Age Min   Age Max   Weight ( Kg ) Route   Dose Min   Dose Max   Unit   Dosage Form   Frequency  Additional Info  
1 Long term suppression of chronic or recurrent, uncomplicated, lower urinary-tract infections and asymptomatic bacteriuria. up to 6Year Oral 18 mg/kg Tablet q.i.d.
2 Long term suppression of chronic or recurrent, uncomplicated, lower urinary-tract infections and asymptomatic bacteriuria. 6 Year 12 Year Oral 500 mg Tablet q.i.d.

Ref :- Book : Martindale    Page : 323   Edition : 38,
►  Side Effect : gastrointestinal disturbance, nausea, vomiting, diarrhoea, Skin rashes, pruritus, Irritation, Inflammation of the urinary tract, especially the bladder, as well as painful and frequent micturition, haematuria, and proteinuria,
Ref :-   Book : Martindale    Page : 323   Edition : 38,

►  Drug Interaction : Drug interaction of Methenamine is with Antacid , , Thiazide Diuretics ,  Acetazolamide, Sulfonamide,
Ref :-   Book : Martindale    Page : 323   Edition : 38,


  ►    Mechanism of Drug Drug Interaction :  The use of drugs that alkalinise the urine, including some antacids, potassium citrate, and diuretics such as acetazolamide or the thiazides, should be avoided because the activation of methenamine to formaldehyde may be inhibited. Use of methenamine with sulfonamides may increase the risk of crystalluria since methenamine requires low urinary pH for its effect, at which sulfonamides and their metabolites are poorly soluble; methenamine may also form poorly soluble compounds with some sulfonamides. ,
Ref :-   Book : Martindale    Page : 323   Edition : 38,


►  Contraindication : hepatic impairment, severe dehydration, metabolic acidosis, or gout.,
Ref :-   Book : Martindale    Page : 323   Edition : 38,
  ►  Mechanism of Action :   Urea-splitting organisms such as Proteus and some Pseudomonas spp. tend to increase urinary pH and inhibit the release of formaldehyde, thereby decreasing the effectiveness of methenamine.,
Ref :-   Book : Martindale    Page : 323   Edition : 38,

Pathway of Dietry Product


​   ► Act.Comp / Nutrient / Food / Herb as follows :- NA


Dietry Substance Interactions


​   ► This Medicine interact with :- NA



ContraIndication Dietry Substance


​   ► This Medicine contraindicate with :- NA

►   Route of Elimination :   Renal,
Ref :-   Book : Martindale    Page : 323   Edition : 38,


►    Plasma Half-life :
  Min value :-   4 hours,    Max value :-   NA
Ref :-   Book : Martindale    Page : 323   Edition : 38,

►    Peak Plasma Concentration :   Min value :-   2 hours,    Max value :-   NA
Ref :-   Book : Martindale    Page : 323   Edition : 38,