Methenamine

Drug #1241

Methenamine used as a topical antiseptic and for urinary tract infections.

Primary Characteristics

It is of Synthetic origin.

Molecular Weight: 140.2 · Solubility in Water: 1 in 1.5 · Solubility in Alcohol: 1 in 12.5 · Non-proprietary name: Methenamine · pH: 6.

Pharmacokinetics

Elimination: plasma half-life is 4 hr.

Indications

Methenamine is primarily indicated in conditions like Cytotoxic-induced neutropenia, Long-term treatment of healed gastro-oesophageal reflux disease, Urinary tract infection.

Methenamine is also indicated for secondary conditions like Drying secretions, amnesia.

Contraindications

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

Dosage

Methenamine's dosage details are as follows:

Dose	Single Dose	Frequency	Route	Instructions
Adult Dosage
1 g	1 g	Every 12h	PO	May be increased upto 3 times daily.
75 mg	75 mg	Every 24h	PO	For UTI Prophylaxis, at bed time
Paediatric Dosage (20kg)
0.5 g	0.5 g	—		4 times daily in those aged 6 to 12 year
18 mg/kg	18 mg/kg	—		18 mg/kg body weight four times daily has been suggested in children up to 6 year of age
Neonatal Dosage (3kg)
No data.

Drug Interactions

3 interactions

Always consult your physician for the change of dose regimen or an alternative drug of choice that may strictly be required.

Side Effects

The signs and symptoms that are produced after acute overdosage of Methenamine are Diarrhea, Hematuria, Nausea & vomiting, Proteinuria, Inflamation of bladder, Painful micturition.

Methenamine is known to cause more or less tolerable side effects which are usually transient. These include Diarrhea, Hypersensitivity , Nausea and vomiting, Pruritus , Skin RashX.

Warnings / Precautions

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.

Interference in Pathology

Methenamine may interfere in the diagnosis of Interference with lab estimation for catecholamines,17-hydroxycorticosteroides & oestrogen in urine.

Available Brands

None recorded.

Storage Conditions

Methenamine should be stored Tab, Elixir, Oral soln , Oral susp.

Drug Classification

1.6.2.2.11 — Methenamine