methenamine/methylene blue/ hyoscyamine/ sodium phosphate monobasic/ phenyl salicylate

Action and Spectrum

Actions and spectrum: 

• methenamine: methenamine is an antibacterial agent that works by converting to formaldehyde in the urine, creating an acidic environment which inhibits the growth of bacteria in the urinary tract. It is primarily effective against gram-positive and some gram-negative bacteria. 
• hyoscyamine: hyoscyamine is an anticholinergic medication that helps relieve urinary symptoms associated with UTIs, such as urgency, frequency, and bladder spasms. It acts by blocking the acetylcholine, a neurotransmitter involved in bladder muscle contractions. 
• methylene Blue: methylene blue is a urinary tract analgesic that provides relief from pain and burning sensations during urination. It acts as a local anesthetic on the mucous membranes of the urinary tract. 
• phenyl Salicylate: phenyl salicylate is a nonsteroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic properties. It helps reduce inflammation, relieve pain, and lower fever associated with UTIs. 
• sodium phosphate monobasic: sodium phosphate monobasic is a urinary acidifier that helps lower the pH of urine. This acidification can prevent the growth and multiplication of certain bacteria in the urinary tract. 

The combination of these components in the medication aims to provide antibacterial action, relief of urinary symptoms, pain relief, and urinary acidification to treat UTIs comprehensively. 

Drug Interaction

Adverse Reaction

Frequency defined 

1-10% 

hyoscyamine 

• Constipation 
• Dysguesia 
• Blurred vision 
• Dysphagia

methenamine 

• Rash 
• Nausea 
• Pruritus 
• Dyspepsia 
• Vomiting

methylene blue 

• Paresthesia 
• Headache 
• Musculoskeletal pain

>10% 

methylene blue 

• Limb pain 
• Feeling hot 
• stool and urine discoloration 
• Skin discoloration

hyoscyamine 

• Dry skin

<1% 

hyoscyamine 

• Tachycardia 
• Headache

methenamine 

• AST Increased 
• serum ALT Increased

methylene blue 

• Serotonin syndrome

Frequency not defined 

CNS: drowsiness, Dizziness 

Gastrointestinal: Dry mouth 

Anaphylactic reactions 

Cardiovascular: Flushing 

Genitourinary: acute urinary retention, Difficult micturition 

Respiratory: trouble breathing or Shortness of breath 

Black Box Warning

Black Box Warning: 

There is no specific black box warning associated with the combination medication of methenamine, hyoscyamine, methylene blue, phenyl salicylate, and sodium phosphate monobasic. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication: 

• Hypersensitivity or allergy to any of the active ingredients or related compounds. 
• Glaucoma (increased intraocular pressure) or a predisposition to glaucoma. 
• Severe liver disease or impairment. 
• Severe kidney disease or impairment. 
• Urinary tract obstruction or urinary retention. 
• Severe gastrointestinal disorders or obstructive disorders of the gastrointestinal tract. 
• Severe cardiac or cardiovascular conditions, such as severe coronary artery disease or congestive heart failure. 
• Known or suspected ileus (bowel obstruction) or paralytic ileus.

Caution: 

• Elderly patients: Use caution in elderly individuals, as they may be more susceptible to certain side effects or complications. 
• Cardiovascular conditions: Use caution in patients with cardiovascular diseases, such as arrhythmias, congestive heart failure, or coronary artery disease, as the medication may have potential effects on the cardiovascular system. 
• Gastrointestinal disorders: caution should be used in patients with gastrointestinal disorders, such as gastric ulcers or intestinal obstruction, as the medication may worsen these conditions. 
• Angle-closure glaucoma: Use caution in patients with a history of or predisposition to angle-closure glaucoma, as the medication may increase intraocular pressure. 
• Asthma or COPD: Use caution in patients with respiratory conditions, as the medication may have potential effects on the respiratory system. 
• Hypertension: Use caution in patients with high blood pressure, as the medication may have potential effects on blood pressure.

Comorbidities: 

• Renal impairment: Individuals with impaired kidney function may require dosage adjustments or close monitoring, as some components of the medication may be excreted through the kidneys. 
• Hepatic impairment: Individuals with liver disease or impaired liver function may require dosage adjustments or close monitoring, as some components of the medication may be metabolized in the liver. 
• Glaucoma: Individuals with a history of or predisposition to glaucoma, particularly narrow-angle glaucoma, may need to exercise caution, as the medication may increase intraocular pressure. 
• Urinary obstruction: Individuals with urinary tract obstruction or urinary retention may need to exercise caution, as some components of the medication may affect urinary function. 
• Myasthenia gravis: Individuals with myasthenia gravis, a neuromuscular disorder, may need to be cautious when using medications containing hyoscyamine, as it may worsen muscle weakness. 

Pregnancy / Lactation

Pregnancy consideration: Not assigned 

Lactation: hyoscyamine, methenamine – gets excreted in human milk  

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies show no risk to the fetus in the first or later trimester. 
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women. 
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.   
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

• methenamine: It is a urinary antiseptic that is converted into formaldehyde in an acidic environment. Formaldehyde helps prevent the growth of bacteria in the urinary tract. 
• hyoscyamine: It belongs to a class of medications called anticholinergics. It acts by blocking the acetylcholine, a neurotransmitter, thereby reducing smooth muscle spasm and secretions in the urinary and gastrointestinal tracts. 
• methylene Blue: It is a dye and an oxidation-reduction agent. It has various mechanisms of action, including inhibiting monoamine oxidase (MAO) enzymes, increasing levels of intracellular cGMP, and possessing weak antimalarial properties. 
• phenyl salicylate: It is a salicylate derivative with analgesic and antipyretic properties. It is believed to work by inhibiting the production of certain chemicals called prostaglandins, which are involved in pain and inflammation. 
• sodium phosphate monobasic: It is a buffering agent that helps maintain the pH of the medication and may also have mild laxative effects. 

The combination of these ingredients in the medication aims to provide relief from urinary tract discomfort, such as urgency, frequency, and pain associated with infections or irritations. It may also have antispasmodic effects on the gastrointestinal tract.  

Pharmacodynamics: 

• methenamine: It exerts its pharmacodynamic effect by converting into formaldehyde in an acidic environment. Formaldehyde has antimicrobial properties and acts as a urinary antiseptic by preventing the growth of bacteria in the urinary tract. 
• hyoscyamine: It is an anticholinergic agent that blocks the effects of acetylcholine, a neurotransmitter. By doing so, it reduces smooth muscle spasm and secretions in the urinary and gastrointestinal tracts, providing relief from symptoms such as urgency and frequency. 
• methylene Blue: It has various pharmacological actions, including inhibition of monoamine oxidase (MAO) enzymes, which are involved in the breakdown of neurotransmitters. By inhibiting MAO, methylene blue can increase the levels of these neurotransmitters, potentially affecting mood and mental state. 
• phenyl salicylate: It is a salicylate derivative with analgesic and antipyretic properties. It acts by inhibiting the production of prostaglandins, which are involved in pain and inflammation processes. By reducing prostaglandin levels, phenyl salicylate can help alleviate discomfort and reduce fever. 
• sodium phosphate monobasic: While its specific pharmacodynamic effects may be minimal, sodium phosphate monobasic acts as a buffering agent to maintain pH. 

The combination of these pharmacodynamic effects aims to relieve symptoms associated with urinary tract discomfort, such as pain, urgency, frequency, and spasms. The anticholinergic and antispasmodic effects of hyoscyamine, along with the antimicrobial properties of methenamine, contribute to the relief of urinary tract symptoms. methylene blue and phenyl salicylate may have additional effects on neurotransmitter levels and pain/inflammation pathways, respectively.  

Pharmacokinetics: 

methenamine: 

• Absorption: methenamine is well-absorbed from the gastrointestinal tract. 
• Distribution: It is distributed throughout the body, including the urinary tract. 
• Metabolism: methenamine is converted to formaldehyde in an acidic environment, such as the urinary tract. 
• Excretion: The primary route of excretion is through the kidneys, with formaldehyde being eliminated in the urine. 

hyoscyamine: 

• Absorption: hyoscyamine is well-absorbed from the gastrointestinal tract. 
• Distribution: It is distributed to various tissues throughout the body. 
• Metabolism: hyoscyamine undergoes hepatic metabolism. 
• Excretion: The metabolites of hyoscyamine are primarily eliminated in the urine and feces. 

methylene blue: 

• Absorption: methylene blue is rapidly absorbed from the gastrointestinal tract. 
• Distribution: It is distributed throughout the body, including various tissues. 
• Metabolism: methylene blue undergoes hepatic metabolism. 
• Excretion: The metabolites of methylene blue are excreted in the urine and feces. 

phenyl salicylate: 

• Absorption: phenyl salicylate is well-absorbed from the gastrointestinal tract. 
• Distribution: It is distributed throughout the body. 
• Metabolism: phenyl salicylate undergoes hepatic metabolism. 
• Excretion: The metabolites of phenyl salicylate are excreted in the urine. 

sodium phosphate monobasic: 

• Absorption: sodium phosphate monobasic is well-absorbed from the gastrointestinal tract. 
• Distribution: It is distributed throughout the body. 
• Metabolism: sodium phosphate monobasic undergoes minimal metabolism. 
• Excretion: It is primarily excreted in the urine. 

Adminstartion

Administration: 

• Route of Administration: The combination medication may be available in various forms, such as tablets, capsules, or oral solutions. The specific form and route of administration will depend on the formulation. 
• Dosage: The dosage of the combination medication will depend on the individual components and the condition being treated. It is important to take the medication as prescribed by your healthcare provider and follow the recommended dosage instructions. 
• Timing: The timing of administration may depend on the specific instructions provided with the medication. It is important to follow the recommended dosing schedule, which may involve taking the medication with or without food. 
• Duration of Treatment: The combination medication depends on the condition being treated and the response to therapy. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: methenamine/methylene blue/hyoscyamine/sodium phosphate monobasic/phenyl salicylate 

Pronounced: (METH-uh-NAM-een / METH-uh-leen bloo / HYE-oh-SYE-uh-meen / SO-dee-um FOS-fate mon-oh-BAY-sik-uhl / FEE-nuhl sal-i-SIL-ate) 

Why do we use methenamine, hyoscyamine, methylene blue, phenyl salicylate and sodium phosphate monobasic? 

• methenamine: It is a urinary tract antiseptic that helps to prevent growth of the bacteria in the urine. It is used to treat and prevent UTIs. 
• hyoscyamine: It is an anticholinergic medication that helps to reduce muscle spasms in the urinary tract. It is used to relieve symptoms such as urinary urgency, frequency, and bladder spasms associated with UTIs. 
• methylene blue: It is a dye and urinary tract antiseptic that helps to prevent the growth of bacteria in the urine. It is used to treat and prevent UTIs. 
• phenyl salicylate: It is an antipyretic and analgesic medication which helps to relieve pain and reduce fever. It may provide symptomatic relief for UTIs. 
• sodium phosphate monobasic: It is a urinary acidifier that helps to lower the pH of the urine, making it less favourable for bacterial growth. It is used to enhance the effectiveness of other medications in the treatment of UTIs.