Ammonium Chloride + Diphenhydramine + Sodium Citrate + Terpin Hydrate

Usage

This combination medication is primarily prescribed for the symptomatic relief of cough associated with the common cold, bronchitis, and other upper respiratory tract infections. It is particularly effective for coughs productive of mucus. It may also be used to treat dry cough, smoker’s cough, whooping cough, chronic cough, and post-surgical cough.

Pharmacological Classification: Expectorant, antihistamine, antitussive, mucolytic.

Mechanism of Action: This combination medication works through multiple pathways to relieve cough symptoms. Ammonium chloride and terpin hydrate act as expectorants, thinning and loosening mucus in the airways to facilitate easier expectoration. Diphenhydramine, an antihistamine, dries secretions, reduces sneezing, itching, and watery eyes. It also has mild antitussive (cough-suppressing) properties. Sodium citrate acts as a mucolytic agent, further helping to break down and thin mucus.

Alternate Names

There’s no official alternate name for this specific combination. It’s often referred to as an “expectorant and antihistamine combination.” Brand names may vary depending on the manufacturer and region (e.g., Torex, Aden-Rex, A Rex, Respy-TR).

How It Works

Pharmacodynamics: The combined action of the ingredients thins mucus, suppresses cough, and dries up excessive secretions.

Pharmacokinetics:

• Absorption: Orally administered components are absorbed from the gastrointestinal tract.
• Metabolism: Primarily hepatic metabolism, especially for diphenhydramine. Ammonium chloride is metabolized in the liver to urea and hydrochloric acid.
• Elimination: Primarily renal excretion for all components.

Mode of Action:

• Ammonium chloride and terpin hydrate: Increase respiratory tract fluid secretions through vagal gastric reflex stimulation, thus decreasing mucus viscosity.
• Diphenhydramine: Antagonizes histamine H1 receptors, reducing allergic symptoms and exerting antitussive effects.
• Sodium citrate: Alkalinizes respiratory secretions, making mucus less viscous.

Dosage

Standard Dosage

Adults: 5-10 mL (1-2 teaspoons) every 4-6 hours as needed. The maximum daily dose should not exceed 60 mL.

Children: Dosage is based on weight or age. Consult a healthcare professional for specific pediatric dosing guidelines. This combination is generally not recommended for children under 6 years of age. Doses for older children vary depending on specific product formulation; some range from 2.5 mL to 5 mL every 4 hours.

Special Cases:

• Elderly Patients: Begin with a lower dose due to potential age-related decline in renal and hepatic function and titrate upwards as needed.
• Patients with Renal Impairment: Dose adjustment is necessary. Consult a nephrologist for appropriate guidance.
• Patients with Hepatic Dysfunction: Dose adjustment may be required. Consult a hepatologist for recommendations.
• Patients with Comorbid Conditions: Use cautiously in patients with glaucoma, prostatic hypertrophy, cardiovascular disease, or other conditions potentially exacerbated by anticholinergic effects. Close monitoring is crucial.

Clinical Use Cases

Dosage recommendations for specific clinical settings like intubation, surgical procedures, mechanical ventilation, ICU use, and emergency situations are not explicitly defined for this particular combination. Dosage should be tailored to the patient’s individual needs under the guidance of a medical professional.

Side Effects

Common Side Effects

• Drowsiness
• Dizziness
• Dry mouth, nose, and throat
• Nausea and vomiting
• Headache
• Fatigue
• Blurred vision
• Constipation
• Difficulty urinating

Rare but Serious Side Effects

• Allergic reactions (rash, itching, swelling)
• Difficulty breathing or swallowing
• Confusion
• Hallucinations
• Seizures

Long-Term Effects

Chronic complications are rare with short-term use. Long-term use can lead to tolerance to the antihistamine effect and potential anticholinergic effects like cognitive impairment.

Contraindications

• Hypersensitivity to any component
• Narrow-angle glaucoma
• Urinary retention (e.g., due to prostatic hypertrophy)
• Severe respiratory conditions (e.g., asthma, COPD)
• Concomitant use of MAO inhibitors

Drug Interactions

• CNS depressants (alcohol, sedatives, opioids): Additive sedative effects
• Anticholinergic drugs: Increased risk of anticholinergic side effects
• MAO inhibitors: Potential for severe hypertension
• Antidepressants (TCAs): Enhanced anticholinergic adverse reactions
• Beta-blockers (e.g. metoprolol): Diphenhydramine may increase their sedative effects via CYP2D6 inhibition
• Antihypertensives: Potential additive hypotensive effects

Pregnancy and Breastfeeding

• Pregnancy: Consult a healthcare professional before use during pregnancy, as diphenhydramine can cross the placenta. Use only if the benefits outweigh the potential risks.
• Breastfeeding: Diphenhydramine is excreted in breast milk and is generally not recommended during breastfeeding.

Drug Profile Summary

• Mechanism of Action: Expectorant, antihistamine, antitussive, and mucolytic effects
• Side Effects: Drowsiness, dizziness, dry mouth, nausea, constipation.
• Contraindications: Hypersensitivity, glaucoma, urinary retention, severe respiratory disease, concomitant MAO inhibitor use.
• Drug Interactions: CNS depressants, anticholinergics, MAO inhibitors.
• Pregnancy & Breastfeeding: Use with caution. Consult a physician.
• Dosage: Adults: 5-10 mL every 4-6 hours. Children: Consult a healthcare professional.
• Monitoring Parameters: Respiratory status, mental status, and potential adverse effects.

Popular Combinations

This specific combination is itself a common formulation. Other combinations for cough and cold may include decongestants, analgesics, and antipyretics, though combining with these requires careful consideration of potential drug interactions.

Precautions

• General Precautions: Pre-screening for allergies, underlying medical conditions (e.g. kidney or liver disease, breathing problems, glaucoma, bladder problems, or prostate problems) is essential.
• Pregnant Women: Potential risks should be carefully weighed against benefits.
• Breastfeeding Mothers: Neonatal exposure through breast milk is possible.
• Children & Elderly: Age-specific dosing and close monitoring are necessary.
• Lifestyle Considerations: Avoid alcohol, as it may potentiate drowsiness. Avoid driving or operating machinery if drowsiness occurs.

FAQs (Frequently Asked Questions)

Q1: What is the recommended dosage for Ammonium Chloride + Diphenhydramine + Sodium Citrate + Terpin Hydrate?

A: Adults: 5-10 mL (1-2 teaspoons) every 4-6 hours, not exceeding 60 mL in 24 hours. Children’s dosages should be determined by a healthcare professional based on their age and weight.

Q2: Can I drive while taking this medication?

A: No, this medication can cause drowsiness. Avoid driving or operating machinery while taking it.

Q3: What should I do if I miss a dose?

A: Take the missed dose as soon as you remember, unless it’s almost time for your next dose. Do not double the dose.

Q4: Can this medication be used during pregnancy or breastfeeding?

A: Consult with a healthcare professional before using this medication during pregnancy or breastfeeding. The potential risks to the fetus or infant should be weighed against the mother’s benefit.

Q5: What are the common side effects?

A: Common side effects include drowsiness, dizziness, dry mouth, nausea, constipation, headache, and fatigue.

Q6: Are there any serious side effects I should be aware of?

A: Rare but serious side effects include allergic reactions, difficulty breathing, confusion, hallucinations, and seizures. Seek immediate medical attention if these occur.

Q7: Can I take this medication with other medications?

A: Inform your doctor about all other medications you are taking, including over-the-counter drugs and supplements. This combination can interact with certain medications, such as CNS depressants, anticholinergics, and MAO inhibitors.

Q8: How should this medication be stored?

A: Store in a cool, dry place away from direct sunlight and out of reach of children.

Q9: What are the contraindications for this medication?

A: Contraindications include hypersensitivity to any component, narrow-angle glaucoma, urinary retention, severe respiratory disease, and concomitant use of MAO inhibitors.

Q10: What should I tell my patients about lifestyle modifications while on this medicine?

A: Patients should stay hydrated, gargle with warm salt water to soothe the throat, and avoid cough irritants like smoke and dust. They should avoid alcohol while taking this medication. Quitting smoking is recommended for smokers experiencing coughs.