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Registry Hub
Peer-Reviewed Evidence
HomeDrug RegistryCompareAMMONIUM CHLORIDE 2 14 vs ACETAMINOPHEN ASPIRIN AND CAFFEINE
Comparative Pharmacology

AMMONIUM CHLORIDE 2 14 vs ACETAMINOPHEN ASPIRIN AND CAFFEINE Comparison

Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.

Clinical EssentialsPharmacokineticsSpecial PopulationsSafety & MonitoringPregnancy & LactationClinical Insights
Differential Analysis

AMMONIUM CHLORIDE 2.14% vs ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.

View AMMONIUM CHLORIDE 2.14% Monograph View ACETAMINOPHEN, ASPIRIN AND CAFFEINE Monograph
AMMONIUM CHLORIDE 2.14%
Expectorant/Systemic Acidifier
Category C
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
NSAID / Antiplatelet
Category D/X
TL;DR — Key Differences
  • Drug class: AMMONIUM CHLORIDE 2.14% is a Expectorant/Systemic Acidifier; ACETAMINOPHEN, ASPIRIN AND CAFFEINE is a NSAID / Antiplatelet.
  • Half-life: AMMONIUM CHLORIDE 2.14% has a half-life of 4-6 hours; prolonged in renal impairment (up to 12-15 hours).; ACETAMINOPHEN, ASPIRIN AND CAFFEINE has Acetaminophen: 2-4 hours (prolonged in liver disease); aspirin: 15-20 minutes (active metabolite salicylate: 2-3 hours at low doses, prolonged to 15-30 hours at high doses); caffeine: 3-6 hours (prolonged in pregnancy, liver disease)..
  • No direct drug-drug interaction has been documented between AMMONIUM CHLORIDE 2.14% and ACETAMINOPHEN, ASPIRIN AND CAFFEINE.
  • Pregnancy: AMMONIUM CHLORIDE 2.14% is rated Category C; ACETAMINOPHEN, ASPIRIN AND CAFFEINE is rated Category D/X.

Last clinically reviewed: July 2026 · OpiCalc Medical Review Team

Clinical Essentials

AMMONIUM CHLORIDE 2.14%
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Mechanism of Action
AMMONIUM CHLORIDE 2.14%

Ammonium chloride is an acidifying agent. It dissociates into ammonium and chloride ions. The ammonium ion is metabolized in the liver to urea and hydrogen ions, leading to metabolic acidosis. This reduces blood p H and increases renal excretion of alkaline urine.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: weak COX-1/2 inhibitor, analgesic and antipyretic through central action; Aspirin: irreversible COX-1/2 inhibitor, anti-inflammatory, analgesic, antipyretic, antiplatelet; Caffeine: adenosine receptor antagonist, CNS stimulant, enhances analgesic effect.

Indications
AMMONIUM CHLORIDE 2.14%

Treatment of metabolic alkalosis,Urinary acidification to enhance excretion of weak bases (e.g., amphetamines, quinidine) or to promote dissolution of calcium phosphate stones

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

FDA-approved: Temporary relief of minor aches and pains (headache, muscle ache, toothache, backache, menstrual cramps), reduction of fever.,Off-label: None commonly accepted.

Standard Dosing
AMMONIUM CHLORIDE 2.14%

For metabolic alkalosis: 1.5 to 3 g (approximately 280 to 560 m Eq) intravenously over 4 to 6 hours; adjust based on serum chloride and p H.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

1-2 tablets (250 mg acetaminophen, 250 mg aspirin, 65 mg caffeine per tablet) orally every 4-6 hours as needed for pain or fever; maximum 8 tablets per 24 hours.

Direct Interaction
AMMONIUM CHLORIDE 2.14%
No Direct Interaction
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
No Direct Interaction

Pharmacokinetics

AMMONIUM CHLORIDE 2.14%
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Half-Life
AMMONIUM CHLORIDE 2.14%

4-6 hours; prolonged in renal impairment (up to 12-15 hours).

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: 2-4 hours (prolonged in liver disease); aspirin: 15-20 minutes (active metabolite salicylate: 2-3 hours at low doses, prolonged to 15-30 hours at high doses); caffeine: 3-6 hours (prolonged in pregnancy, liver disease).

Metabolism
AMMONIUM CHLORIDE 2.14%

Converted to urea and hydrogen ions in the liver via the urea cycle.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: primarily hepatic via glucuronidation (UGT1A1, UGT1A6, UGT1A9), sulfation (SULT1A1), and minor CYP2E1 (toxic metabolite NAPQI); Aspirin: hydrolyzed to salicylate, further metabolized by conjugation (glycine, glucuronic acid) and oxidation; Caffeine: hepatic via CYP1A2 (major), CYP2E1, CYP3A4, N-acetyltransferase.

Excretion
AMMONIUM CHLORIDE 2.14%

Renal: >99% as ammonium ion and chloride; minimal biliary/fecal elimination.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: renal elimination of metabolites (glucuronide 60%, sulfate 30%, cysteine/mercapturate 8%, unchanged 2%); aspirin: renal elimination of salicylate and metabolites (75% salicyluric acid, 10% glucuronides, 10% salicylate); caffeine: renal elimination of metabolites (paraxanthine, theobromine, theophylline; <3% unchanged). Total: >95% renal.

Protein Binding
AMMONIUM CHLORIDE 2.14%

Negligible (<1%); not significantly bound to plasma proteins.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: 10-25% (albumin); aspirin: 80-90% (albumin, decreased at high doses); caffeine: 35% (albumin).

VD (L/kg)
AMMONIUM CHLORIDE 2.14%

0.3-0.5 L/kg; distributes primarily in extracellular fluid; clinical meaning: low Vd reflects limited tissue penetration.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: 0.9-1.0 L/kg; aspirin: 0.15-0.2 L/kg (low); caffeine: 0.6-0.8 L/kg. Reflects distribution into total body water.

Bioavailability
AMMONIUM CHLORIDE 2.14%

Oral: 100% (fully absorbed); IV: 100%; topical: non-systemic.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: oral 85-98%; aspirin: oral 50-80% (due to first-pass hydrolysis); caffeine: oral ~100%.

Special Populations

AMMONIUM CHLORIDE 2.14%
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Renal Adjustments
AMMONIUM CHLORIDE 2.14%

Contraindicated in severe renal impairment (GFR <30 m L/min). For GFR 30-60 m L/min: reduce dose by 50% and monitor serum electrolytes. For GFR >60 m L/min: no adjustment.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Contraindicated in severe renal impairment (Cr Cl <10 m L/min). For Cr Cl 10-50 m L/min: avoid aspirin component; consider alternative therapy. For Cr Cl >50 m L/min: no adjustment needed for acetaminophen; aspirin may require dose reduction or monitoring.

Hepatic Adjustments
AMMONIUM CHLORIDE 2.14%

No specific Child-Pugh based adjustment; use caution in severe hepatic impairment due to risk of ammonia toxicity.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Child-Pugh A: caution with acetaminophen (max 2 g/day) and avoid caffeine if severe. Child-Pugh B: avoid aspirin; reduce acetaminophen dose (max 2 g/day) and limit caffeine. Child-Pugh C: contraindicated due to aspirin and acetaminophen risk.

Pediatric Dosing
AMMONIUM CHLORIDE 2.14%

Neonates and children: 1-2 m Eq/kg intravenously per dose, infused over 2-4 hours; maximum 100 m Eq per dose. Titrate based on serum chloride and acid-base status.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Not recommended for children <12 years due to aspirin risk of Reye's syndrome. For adolescents ≥12 years: same as adult dosing: 1-2 tablets every 4-6 hours, max 8 tablets/24 hours.

Geriatric Dosing
AMMONIUM CHLORIDE 2.14%

Start at lower end of adult dosing (e.g., 1.5 g intravenously) due to age-related decreased renal function; monitor electrolytes and renal function closely.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Caution due to increased sensitivity to aspirin (GI bleeding, renal impairment) and caffeine (insomnia, tachycardia). Start at low end of dosing: 1 tablet every 6 hours; monitor renal function and avoid long-term use.

Safety & Monitoring

AMMONIUM CHLORIDE 2.14%
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Black Box Warnings
AMMONIUM CHLORIDE 2.14%
FDA Black Box Warning

None

ACETAMINOPHEN, ASPIRIN AND CAFFEINE
FDA Black Box Warning

Reye syndrome warning: Aspirin should not be used in children or teenagers with viral illnesses due to risk of Reye syndrome.

Warnings/Precautions
AMMONIUM CHLORIDE 2.14%

Avoid in patients with impaired renal or hepatic function; may cause hyperammonemia and hepatic coma.,Use with caution in patients with cardiac failure or pulmonary edema due to risk of fluid overload.,Monitor serum chloride, bicarbonate, and p H levels during therapy.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Hepatotoxicity (acetaminophen overdose), gastrointestinal bleeding (aspirin), Reye syndrome (aspirin in children with viral illness), cardiovascular risk (aspirin may increase bleeding), caffeine-related CNS stimulation, risk of dependence.

Contraindications
AMMONIUM CHLORIDE 2.14%

Severe hepatic insufficiency,Severe renal impairment,Hyperammonemia,Uremia,Ammonium toxicity

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Hypersensitivity to any component; active peptic ulcer disease; bleeding disorders; severe hepatic impairment; children/adolescents with viral illness (Reye syndrome); third trimester of pregnancy (aspirin); concurrent use of other salicylates or NSAIDs; severe renal impairment.

Adverse Reactions
AMMONIUM CHLORIDE 2.14%
Data Pending
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Data Pending
Food Interactions
AMMONIUM CHLORIDE 2.14%

No significant food interactions known. However, a diet low in chloride may reduce efficacy. Avoid excessive intake of alkalinizing foods (e.g., citrus fruits, vegetables) that may counteract the acidifying effect.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Alcohol increases risk of hepatotoxicity with acetaminophen and GI bleeding with aspirin. Caffeine-containing foods or beverages should be limited to avoid excessive caffeine intake. High-tyramine foods (e.g., aged cheeses, cured meats) may potentiate caffeine effects; no significant interaction documented.

Pregnancy & Lactation

AMMONIUM CHLORIDE 2.14%
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Teratogenic Risk
AMMONIUM CHLORIDE 2.14%

Ammonium chloride is not known to be teratogenic in humans. No structural anomalies have been reported with first trimester exposure. In second and third trimesters, maternal acidosis from excessive dosing could potentially affect fetal acid-base balance, but no specific fetal risks are documented. Overall, classified as FDA Pregnancy Category C.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

First trimester: Aspirin is associated with increased risk of neural tube defects and cardiac malformations; acetaminophen is considered low risk but some studies suggest possible association with gastroschisis. Second trimester: Aspirin may increase risk of intracranial hemorrhage; acetaminophen and caffeine generally not linked to major malformations. Third trimester: Aspirin use is contraindicated due to risk of premature ductus arteriosus closure and oligohydramnios; high-dose acetaminophen may cause oligohydramnios; caffeine metabolism slows, but moderate intake appears safe; chronic high-dose caffeine may be associated with low birth weight.

Lactation Summary
AMMONIUM CHLORIDE 2.14%

Excretion into breast milk is unknown. M/P ratio not available. Caution advised due to potential for neonatal acidosis if maternal doses are high. Short-term use is likely compatible with breastfeeding.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: M/P ratio approximately 0.9; small amounts excreted; considered safe. Aspirin: M/P ratio variable, typically 0.12-0.42; avoid high doses due to risk of Reye's syndrome; single doses unlikely harmful. Caffeine: M/P ratio approximately 0.5-1.0; moderate intake (≤300 mg/day) considered safe; excessive intake may cause irritability in infant.

Pregnancy Dosing
AMMONIUM CHLORIDE 2.14%

No specific dosing adjustments required in pregnancy. However, due to pregnancy-associated hyperventilation and renal changes, monitor acid-base status. Initiate at low doses and titrate based on serum chloride and bicarbonate levels.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen: No dose adjustment needed; standard dosing (650-1000 mg every 4-6 hours, max 3000 mg/day). Aspirin: Avoid doses >81 mg/day in third trimester; use lowest effective dose. Caffeine: Metabolism prolonged; limit to ≤200 mg/day (approximately 2 cups coffee).

Maternal Safety Status
AMMONIUM CHLORIDE 2.14%
Category C
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Category D/X

Clinical Insights

AMMONIUM CHLORIDE 2.14%
ACETAMINOPHEN, ASPIRIN AND CAFFEINE
Clinical Pearls
AMMONIUM CHLORIDE 2.14%

Ammonium chloride 2.14% is a systemic acidifying agent used to treat metabolic alkalosis. Monitor serum electrolytes (especially chloride and bicarbonate) and arterial blood gases closely. Avoid in patients with severe hepatic or renal impairment, as ammonium ions can precipitate hepatic encephalopathy or worsen acidosis. Infuse slowly to prevent hemolysis. Use with caution in patients with respiratory acidosis.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Acetaminophen, aspirin, and caffeine combination is used for mild to moderate pain and fever reduction. Aspirin component provides anti-inflammatory effects; caution in patients with bleeding disorders or those on anticoagulants due to increased bleeding risk. Acetaminophen hepatotoxicity risk with doses >4g/day or in liver disease. Caffeine may cause insomnia, tremor, or palpitations; avoid in patients with anxiety disorders. Reye syndrome risk with aspirin use in children with viral illnesses. Monitor renal function in elderly or dehydrated patients.

Patient Counseling
AMMONIUM CHLORIDE 2.14%

This medication is used to treat low acid levels in the blood.,Your healthcare provider will monitor your blood tests regularly while on this medicine.,Report any signs of allergic reaction (rash, itching, swelling) or symptoms of acidosis (confusion, rapid breathing) immediately.,Avoid taking other medications or supplements without consulting your doctor, as they may interfere with this treatment.,Do not stop this medication abruptly without medical advice.

ACETAMINOPHEN, ASPIRIN AND CAFFEINE

Do not exceed recommended dose; acetaminophen overdose can cause liver damage.,Avoid alcohol while taking this medication.,Do not use in children or teenagers with viral illnesses due to Reye syndrome risk.,May cause stomach upset; take with food or milk.,Limit caffeine intake from other sources when using this medication.

Safety Verification

Known Interactions

AMMONIUM CHLORIDE 2.14% Risks3
Ammonium chloride + Lisdexamfetamine
moderate

"Ammonium chloride, an acidifying agent, reduces urinary pH, which increases the renal clearance of lisdexamfetamine and its active metabolite d-amphetamine. This accelerated elimination leads to decreased systemic exposure and potentially diminished therapeutic efficacy of lisdexamfetamine. Clinically, patients may experience reduced symptom control for ADHD or binge eating disorder, requiring dose adjustments or alternative therapies."

Sufentanil + Ammonium chloride
moderate

"Sufentanil, a potent opioid analgesic, may increase renal excretion of ammonium chloride by promoting diuresis through opioid-induced release of antidiuretic hormone (ADH) and subsequent water reabsorption, leading to dilutional acidosis and enhanced ammonium excretion. This interaction can result in reduced serum ammonium levels and decreased efficacy of ammonium chloride as an acidifying agent, potentially compromising its therapeutic effect in metabolic alkalosis or urinary tract infections. Clinical outcomes may include incomplete correction of metabolic alkalosis or reduced antimicrobial activity of ammonium chloride in the urine."

Ammonium chloride + Amphetamine
moderate

"Ammonium chloride acidifies the urine, which increases the renal excretion of amphetamine by favoring its ionized form in the tubular lumen, thereby reducing its reabsorption. This leads to a decreased serum concentration of amphetamine and potentially diminished therapeutic efficacy. Clinically, patients may experience reduced mood-elevating or stimulant effects, requiring dose adjustment."

ACETAMINOPHEN, ASPIRIN AND CAFFEINE Risks3
Triamterene + Caffeine
moderate

"Triamterene, a potassium-sparing diuretic, can inhibit the hepatic metabolism of caffeine by competing for cytochrome P450 (CYP) 1A2, the primary enzyme responsible for caffeine clearance. This leads to increased plasma caffeine concentrations and prolonged caffeine half-life, potentially causing caffeine toxicity manifesting as nervousness, insomnia, tachycardia, and diuresis enhancement. Patients may experience exaggerated stimulant effects and increased risk of cardiac arrhythmias when combining these agents."

Caffeine + Sulfadiazine
moderate

"Caffeine inhibits the metabolism of sulfadiazine by competitively antagonizing cytochrome P450 (CYP) enzymes, particularly CYP1A2, leading to increased plasma concentrations of sulfadiazine. This elevates the risk of dose-dependent adverse effects, including crystalluria, nephrotoxicity, and hypersensitivity reactions. The interaction may also reduce the therapeutic efficacy of sulfadiazine due to altered pharmacokinetics."

Caffeine + Losartan
moderate

"Caffeine inhibits the cytochrome P450 enzyme CYP2C9, which is primarily responsible for the metabolism of losartan to its active metabolite E-3174. This inhibition can lead to increased plasma concentrations of losartan and decreased formation of the active metabolite, potentially reducing losartan's antihypertensive efficacy. The clinical outcome may be suboptimal blood pressure control in patients consuming high amounts of caffeine."

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Clinical Q&A

Frequently Asked Questions

Common clinical questions about AMMONIUM CHLORIDE 2.14% vs ACETAMINOPHEN, ASPIRIN AND CAFFEINE, answered by our medical review team.

1. What is the main difference between AMMONIUM CHLORIDE 2.14% and ACETAMINOPHEN, ASPIRIN AND CAFFEINE?

AMMONIUM CHLORIDE 2.14% is a Expectorant/Systemic Acidifier that works by Ammonium chloride is an acidifying agent. It dissociates into ammonium and chloride ions. The ammonium ion is metabolized in the liver to urea and hydrogen ions, leading to metabolic acidosis. This reduces blood p H and increases renal excretion of alkaline urine.. ACETAMINOPHEN, ASPIRIN AND CAFFEINE is a NSAID / Antiplatelet that works by Acetaminophen: weak COX-1/2 inhibitor, analgesic and antipyretic through central action; Aspirin: irreversible COX-1/2 inhibitor, anti-inflammatory, analgesic, antipyretic, antiplatelet; Caffeine: adenosine receptor antagonist, CNS stimulant, enhances analgesic effect.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.

2. Which is stronger: AMMONIUM CHLORIDE 2.14% or ACETAMINOPHEN, ASPIRIN AND CAFFEINE?

Potency comparisons between AMMONIUM CHLORIDE 2.14% and ACETAMINOPHEN, ASPIRIN AND CAFFEINE depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.

3. What is the standard dosing for AMMONIUM CHLORIDE 2.14% vs ACETAMINOPHEN, ASPIRIN AND CAFFEINE?

The standard adult dose of AMMONIUM CHLORIDE 2.14% is: For metabolic alkalosis: 1.5 to 3 g (approximately 280 to 560 m Eq) intravenously over 4 to 6 hours; adjust based on serum chloride and p H.. The standard adult dose of ACETAMINOPHEN, ASPIRIN AND CAFFEINE is: 1-2 tablets (250 mg acetaminophen, 250 mg aspirin, 65 mg caffeine per tablet) orally every 4-6 hours as needed for pain or fever; maximum 8 tablets per 24 hours.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.

4. Can you take AMMONIUM CHLORIDE 2.14% and ACETAMINOPHEN, ASPIRIN AND CAFFEINE together?

No direct drug-drug interaction has been formally documented between AMMONIUM CHLORIDE 2.14% and ACETAMINOPHEN, ASPIRIN AND CAFFEINE in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.

5. Are AMMONIUM CHLORIDE 2.14% and ACETAMINOPHEN, ASPIRIN AND CAFFEINE safe during pregnancy?

The maternal-fetal safety profiles differ. AMMONIUM CHLORIDE 2.14% is classified as Category C. Ammonium chloride is not known to be teratogenic in humans. No structural anomalies have been reported with first trimester exposure. In second and third trimesters, maternal acido. ACETAMINOPHEN, ASPIRIN AND CAFFEINE is classified as Category D/X. First trimester: Aspirin is associated with increased risk of neural tube defects and cardiac malformations; acetaminophen is considered low risk but some studies suggest possible . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.