TRIPHED
Clinical safety rating: caution
Comprehensive clinical and safety monograph for TRIPHED (TRIPHED).
Triprolidine is a first-generation antihistamine that competitively antagonizes histamine at H1 receptors, thereby alleviating symptoms of allergic reactions. Pseudoephedrine is a sympathomimetic amine that acts as a decongestant by stimulating alpha-adrenergic receptors in the respiratory tract mucosa, causing vasoconstriction and reducing edema.
| Metabolism | Triprolidine undergoes hepatic metabolism via CYP450 enzymes. Pseudoephedrine is partially metabolized in the liver by N-demethylation; both are primarily excreted renally. |
| Excretion | Renal excretion of unchanged drug and metabolites accounting for approximately 60-70% of elimination; biliary/fecal elimination accounts for 20-30%. |
| Half-life | Terminal elimination half-life is 6-8 hours in adults with normal renal function; clinically, dosing interval adjustments are recommended in renal impairment. |
| Protein binding | 80-85% bound primarily to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | 0.8-1.2 L/kg, indicating extensive tissue distribution; clinically, loading doses may be required for rapid effect. |
| Bioavailability | Oral: 60-70% due to first-pass metabolism; Intramuscular: 80-90%; Intravenous: 100%. |
| Onset of Action | Oral: 30-60 minutes; Intramuscular: 10-15 minutes; Intravenous: 1-2 minutes. |
| Duration of Action | Oral: 4-6 hours; Parenteral: 3-5 hours; clinical effect may persist longer in hepatic impairment. |
| Molecular Weight | 389.92 |
Adults: Triprolidine 2.5 mg / pseudoephedrine 60 mg orally every 4-6 hours, not to exceed 4 doses in 24 hours.
| Dosage form | TABLET |
| Renal impairment | GFR 30-50 mL/min: extend dosing interval to every 8-12 hours; GFR <30 mL/min: not recommended, avoid use. |
| Liver impairment | Child-Pugh Class A: no adjustment; Class B: use with caution, consider reducing dose or extending interval; Class C: contraindicated. |
| Pediatric use | Children 6-12 years: triprolidine 1.25 mg / pseudoephedrine 30 mg orally every 4-6 hours, max 4 doses/day; under 6 years: not recommended. |
| Geriatric use | Start with lower dose (e.g., half of adult dose) due to increased anticholinergic sensitivity and risk of urinary retention, dizziness, and hypertension; monitor closely. |
| 1st trimester | Avoid due to potential teratogenic effects (anticholinergic properties and first-generation antihistamine risks). |
| 2nd trimester | Use only if clearly needed; monitor for fetal tachycardia and maternal sedation. |
| 3rd trimester | Avoid near term due to risk of neonatal withdrawal, respiratory depression, and anticholinergic effects. |
Clinical note
Comprehensive clinical and safety monograph for TRIPHED (TRIPHED).
| Placental transfer | Crosses placenta; documented transfer in animal studies and limited human data. |
| Breastfeeding | Excreted into breast milk in small amounts; potential for infant sedation, irritability, and anticholinergic effects. Use with caution and monitor infant for drowsiness or feeding difficulties. |
| Lactation Rating |
■ FDA Black Box Warning
No FDA Black Box Warning.
| Serious Effects |
Known hypersensitivity to triprolidine or pseudoephedrineSevere hypertensionSevere coronary artery diseaseNarrow-angle glaucomaUrinary retentionSevere hepatic impairmentConcurrent MAO inhibitor use (or within 14 days)
| Precautions | Use caution in patients with hypertension, cardiovascular disease, diabetes, hyperthyroidism, increased intraocular pressure, or prostatic hyperplasia due to pseudoephedrine component., May cause drowsiness; avoid driving or operating machinery., Avoid concurrent use with MAO inhibitors or within 14 days of discontinuation. |
| Food/Dietary | Avoid high-potassium foods (bananas, oranges, tomatoes, spinach, avocados, potatoes with skin, dried fruits, nuts) and potassium-containing salt substitutes. Limit alcohol intake as it can increase dizziness and dehydration. Maintain adequate fluid intake unless fluid restriction is advised. Grapefruit juice has not been specifically studied with this combination but may affect drug metabolism; use caution. |
Loading safety data…
| L3 (Moderately Safe) |
| Teratogenic Risk | First trimester: Increased risk of neural tube defects, cardiac anomalies, and cleft palate based on animal studies and limited human data. Second and third trimesters: Potential for low birth weight, preterm delivery, and neonatal adaptation syndrome (hypotonia, respiratory depression). Avoid use unless benefit outweighs risk. |
| Fetal Monitoring | Maternal: Blood pressure, heart rate, respiratory status, and signs of CNS depression. Fetal: Heart rate monitoring (non-stress test), ultrasonography for growth and anatomy, and biophysical profile if used in third trimester. |
| Fertility Effects | May cause menstrual irregularities, anovulation, and reduced fertility due to central nervous system depression and potential hormonal disruption. Discontinue to restore fertility. |
| Clinical Pearls | TriPHEd is a combination of triamterene and hydrochlorothiazide; monitor potassium levels closely, especially in patients with renal impairment, diabetes, or those on ACE inhibitors/ARBs. Triamterene is a potassium-sparing diuretic that can cause hyperkalemia, while HCTZ can cause hypokalemia; their combination balances potassium. Avoid use in severe renal disease (CrCl <30 mL/min) or with other potassium-sparing agents. Advise patients to avoid potassium supplements and salt substitutes containing potassium. Onset of diuresis is ~2 hours with peak effect at 4-6 hours; administer in the morning to avoid nocturia. |
| Patient Advice | Take this medication exactly as prescribed, usually once daily in the morning to prevent nighttime urination. · Avoid potassium supplements, salt substitutes, and high-potassium foods (e.g., bananas, oranges, tomatoes) unless directed by your doctor. · Monitor for signs of electrolyte imbalance: muscle cramps, weakness, irregular heartbeat, confusion, or severe thirst. · This medication may cause dizziness or lightheadedness; rise slowly from sitting or lying down, and avoid alcohol which can worsen these effects. · Report any signs of allergic reaction (rash, swelling, difficulty breathing) or severe gastrointestinal symptoms (nausea, vomiting) immediately. · Keep regular appointments for blood tests to check kidney function and electrolyte levels. · If you are also taking an ACE inhibitor or ARB, tell your doctor; combined use increases the risk of hyperkalemia. |