Me Naphos Mb Hyo 1
81.6 mg + 40.8 mg + 10.8 mg + .12 mg · Tablet
- Prescription only
- Oxidation-Reduction Agent
- Active substance
- Urinary Antiseptic Antispasmodic
- Made by
- Method Pharmaceuticals
- Source
- Official label
Quoted from the official source. Not yet reviewed by Mediclarum — the leaflet in your pack is authoritative.
At a glance
Quoted from the official label · 2025-10-21
Oxidation-Reduction Agent
- ME/NaPhos/MB/Hyo 1 Tablets is indicated for the treatment of symptoms of irritative voiding.
Do not exceed recommended dosage. If rapid pulse, dizziness, or blurring of vision occurs discontinue use immediately.
All warnings ↓- Prescription only
- FDA enforcement reports list no ongoing recall, and none from the last two years, for this product code · checked 2026-10-02
Every line above is selected, not written, from the official label. Nothing is reworded. DailyMed
What it is for
- ME/NaPhos/MB/Hyo 1 Tablets is indicated for the treatment of symptoms of irritative voiding.
- Indicated for the relief of local symptoms, such as hypermotility which accompany lower urinary tract infections and as antispasmodic.
- Indicated for the relief of urinary tract symptoms caused by diagnostic procedures.
From the official label · 2025-10-21 · DailyMed
How it works
From this product’s own US prescribing label.
HYOSCYAMINE is a parasympatholytic which relaxes smooth muscles and thus produces an antispasmodic effect.
It is well absorbed from the gastrointestinal tract and is rapidly distributed throughout body tissues.
Most is excreted in the urine within 12 hours, 13% to 50% being unchanged.
Quoted from the prescribing label, sections “Mechanism of Action” and “Pharmacokinetics”. DailyMed · 2025-10-21
How to take it
These directions are for this exact strength and form. Another one is different.
Adults One tablet orally 4 times per day followed by liberal fluid intake. Older Children Dosage must be individualized by physician. Not recommended for use in children up to 6 years of age.
Quoted from the official label, section “Dosage & Administration”.
Other warnings
- Do not exceed recommended dosage. If rapid pulse, dizziness, or blurring of vision occurs discontinue use immediately.
- (Pregnancy Category C) hyoscyamine and methenamine cross the placenta.
- Studies have not been done in animals or humans.
- It is not known whether ME/NaPhos/MB/Hyo 1 Tablets cause fetal harm when administered to a pregnant woman or can affect reproduction capacity.
- ME/NaPhos/MB/Hyo 1 Tablets should be given to a pregnant woman only if clearly needed.
- 1 Tablet 4 times daily followed by liberal fluid intake, or as directed by a physician.
- FOR FULL PRODUCT INFORMATION SEE ATTACHED BOOKLET.
- Protect from moisture or direct sunlight.
- NOTE :
- Patient should be advised that urine will be colored blue while taking this medication.
- PHARMACIST :
- Preserve and dispense in tight-light resistant container as defined in the USP.
- KEEP THIS AND ALL MEDICINES OUT OF THE REACH OF CHILDREN.
- Tamper evident by heat seal under cap.
- Do not use if there is evidence of tampering.
- To report an adverse event, please contact Method Pharmaceuticals, LLC at (877) 250-3427.
Quoted from the official label, section “Warnings”.
Other medicines
- because of this product's effect on gastrointestinal motility and gastric emptying, it may decrease the absorption of other oral medications during concurrent use such as:
- urinary alkalizers; thiazide diuretics (may cause the urine to become alkaline reducing the effectiveness of methenamine by inhibiting its conversion to formaldehyde); antimuscarinics (concurrent use may intensify antimuscarinic effects of hyoscyamine because of secondary antimuscarinic activities of these medications); antacids/antidiarrheals (may reduce absorption of hyoscyamine, concurrent use with antacids may cause urine to become alkaline reducing effectiveness of methenamine by inhibiting its conversion to formaldehyde) doses of these medications should be spaced 1 hour apart from doses of hyoscyamine; antimyasthenics (concurrent use with hyoscyamine may further reduce intestinal motility); ketoconazole (patients should be advised to take this combination at least 2 hours after ketoconazole); monoamine oxidase (MAO) Inhibitors (concurrent use may intensify antimuscarinic side effects, opioid (narcotic) analgesics may result in increased risk of severe constipation); sulfonamides (these drugs may precipitate with formaldehyde in the urine, increasing the danger of crystalluria).
- Patients should be advised that the urine may become blue to blue green and the feces may be discolored as a result of the excretion of methylene blue.
Quoted from the official label, section “Drug Interactions”.
If you take too much
In an emergency, call your local emergency number or a poison control centre.
- Emesis or gastric lavage.
- Slow intravenous administration of physostigmine in doses of 1 mg to 4 mg (0.5 mg to 1 mg in children), repeated as needed in one to two hours to reverse severe antimuscarinic symptoms.
- Administration of small doses of diazepam to control excitement and seizures.
- Artificial respiration with oxygen if needed for respiratory depression.
- Adequate hydration.
- Symptomatic treatment as necessary.
Quoted from the official label, section “Overdosage”.
Misuse and dependence
A dependence on the use of ME/NaPhos/MB/Hyo 1 Tablets has not been reported and due to the nature of its ingredients, abuse of ME/NaPhos/MB/Hyo 1 Tablets is not expected.
Quoted from the official label, section “Drug Abuse and Dependence”.
Use in children
Pediatric infants and young children are especially susceptible to the toxic effect of the belladonna alkaloids.
Quoted from the official label, section “Pediatric Use”.
Use in older people
with caution in elderly patients as they may respond to usual doses of hyoscyamine with excitement, agitation, drowsiness, or confusion.
Quoted from the official label, section “Geriatric Use”.
Side effects
Cardiovascula r – rapid pulse, flushing Central Nervous System – blurred vision, dizziness Respiratory – shortness of breath or troubled breathing Genitourinary – difficulty micturition, acute urinary retention Gastrointestinal – dry mouth, nausea/vomiting
Quoted from the official label, section “Adverse Reactions”.
Other information
- CAUTION RX ONLY STORAGE
- Store at 25° C (77° F); excursions permitted to 15° C to 30° C (59° F to 86° F) [See USP Controlled Room Temperature]. Keep container tightly closed. Distributed By:
- Method Pharmaceuticals, LLC Arlington, TX 76006 Rev. Date:
- 01/2016
Quoted from the official label, section “OTC — Other Information”.
What it looks like and how it is packed
ME/NaPhos/MB/Hyo 1 Tablets are light blue to blue, oval, biconvex tablets debossed with "M455" with scoreline on one side and plain on the other side. Supplied in bottles of 100 tablets (NDC 58657-454-01).
Quoted from the official label, section “How Supplied”.
Other ingredients
Relevant if you react to a dye, a preservative, lactose or gluten.
- include:
- Microcrystalline Cellulose, Mannitol, Croscarmellose Sodium, Magnesium Stearate, FD&C Blue #1 HYOSCYAMINE SULFATE is an alkaloid of belladonna.
- Exists as a white crystalline powder.
- Affected by light It is very soluble in water; freely soluble in alcohol; practically insoluble in ether.
- METHENAMINE exists as colorless, lustrous crystals or white crystalline powder.
- Its solutions are alkaline to litmus.
- Freely soluble in water; soluble in alcohol and in chloroform.
- METHYLENE BLUE exists as dark green crystals.
- It is soluble in water and in chloroform; sparingly soluble in alcohol.
- MONOBASIC SODIUM PHOSPHAT E exists as a white crystalline powder.
- Its solutions are acidic to litmus.
- It is freely soluble in water and practically insoluble in alcohol.
- This product is not an Orange Book (OB) rated product, therefore all prescriptions using this product shall be pursuant to state statutes as applicable.
- There are no claims of bioequivalence or therapeutic equivalence.
Quoted from the official label, section “Inactive Ingredients”.
What is in it
- Each tablet contains:
- Methenamine, USP ................................. 81.6 mg Monobasic Sodium Phosphate, USP ......... 40.8 mg Methylene Blue ....................................... 10.8 mg Hyoscyamine Sulfate ............................... 0.12 mg
Quoted from the official label, section “Description”.
Ingredients people check for
Lactose, gluten, dyes, sugars and other ingredients that matter with an allergy, intolerance or diet — as this product’s FDA label lists them.
- Colour dyes
FD&C Blue #1 HYOSCYAMINE SULFATE is an alkaloid of belladonna
Some people react to dyes such as tartrazine (Yellow 5) or carmine. - Sugar alcohols
Mannitol
Sorbitol and similar can upset the stomach and matter with fructose intolerance. - Alcohol (ethanol)
freely soluble in alcohol; soluble in alcohol; sparingly soluble in alcohol; practically insoluble in alcohol
Matters for children, in pregnancy, in recovery and with some medicines.
Quoted from the FDA label. A label that does not name an ingredient is not a guarantee that the product is free of it, and formulations change. With an allergy, check the pack and ask a pharmacist.
Details
| Made by | Method Pharmaceuticals |
|---|---|
| Active substance | Urinary Antiseptic Antispasmodic |
| Strength | 81.6 mg + 40.8 mg + 10.8 mg + .12 mg |
| Form | Tablet |
| Route | Oral |
| Packs | 100 TABLET in 1 BOTTLE |
| NDC | 58657-454 |
Source: NDC Directory · 2026-09-13 · not reviewed by a clinician
Source: US Food and Drug Administration, NDC Directory. Reuse terms: US government work (FDA).