Dose: 1 g
Single Dose: 1 (1)
Frequency: 12 hourly
Route: PO
Instructions: May be increased upto 3 times daily.

Dose: 0.5 g
Single Dose: 0.5 (0.5)
Frequency: As recommended.
Route: 4 times daily in those aged 6 to 12 year
Instructions:

. It is of Synthetic origin. . The Molecular Weight of Methenamine is 140.20. It is weakly acidic drug.

Methenamine is contraindicated in conditions like Acidosis,Gout,Dehydration,Hepatic insufficiency.

The signs and symptoms that are produced after the acute overdosage of Methenamine include Diarrhea, Hematuria, Nausea & vomiting, Proteinuria, Inflamation of bladder, Painful micturition.The symptomatic adverse reactions produced by Methenamine are more or less tolerable and if they become severe, they can be treated symptomatically, these include Diarrhea, Pruritus, Skin RashX, Hypersensitivity, Nausea and vomiting.

Methenamine is primarily indicated in conditions like Cytotoxic-induced neutropenia, Long-term treatment of healed gastro-oesophageal reflux disease, Urinary tract infection, and can also be given in adjunctive therapy as an alternative drug of choice in Drying secretions, amnesia.

Methenamine is known to interact with other drugs, the details of drug interactions is as follows:DrugDetailsSeverityOnsetManagementAcetazolamide (Na)Acetazolamide keep urine alkaline and prevent urinary antiseptic effect of methenamineSodium CitrateSodium Citrate may increase the excretion and decrease the serum levels of Methenamine, possibly decreasing their pharmacologic effects.SulphamethizoleIn acid urine, methenamine breaks down into formaldehyde, which may form an insoluble precipitate with certain sulfonamides, especially those that are less soluble in urine, and may also increase the danger of crystalluria.Concurrent use is not recommended. These interactions are sometimes beneficial and sometimes may pose threats to life. Always consult your physician for the change of dose regimen or an alternative drug of choice that may strictly be required.

Interference with lab estimation for catecholamines,17-hydroxycorticosteroides & oestrogen in urine

Drug should not be given to Paediatrics, Pregnant Mothers, Cardiac / Hypertensive Patients, patients suffering from Liver Malfunction, Geriatrics, and Neonates.If prescribing authority justifies the benefits of the drug against the possible damages he/she should reevaluate them and consult the reference material and previous studies.

Tab, Elixir, Oral soln , Oral susp Store . Protect from Sunlight.

It should be used with caution in patients with dehydration, severe renal function impairment (as its salt may precipitate causing crystalluria), hypersensitivity to drug and hepatic function impairments.