Histex PD 0.938mg Drops
Overview
What is this medicine?
How to Use This Medicine
To use this medication safely and effectively, follow your doctor's instructions and read all the information provided. You can take this medication with or without food. If it causes stomach upset, taking it with food may help. When measuring liquid doses, use the measuring device that comes with the medication. If one is not provided, ask your pharmacist for a suitable measuring device.
Storing and Disposing of Your Medication
Store this medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a secure location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of medications, consult your pharmacist. You may also want to check if there are drug take-back programs in your area.
Missing a Dose
If you take this medication regularly and miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or extra doses. If you take this medication as needed, do not take it more frequently than directed by your doctor.
Lifestyle & Tips
- This medication can cause drowsiness. Avoid driving, operating machinery, or engaging in activities requiring mental alertness until you know how it affects you.
- Avoid alcohol consumption while taking this medication, as it can increase drowsiness and other side effects.
- Stay hydrated to help with dry mouth, a common side effect.
- For children, ensure accurate dosing using the provided dropper to prevent accidental overdose.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Pediatric Dosing
Dose Adjustments
Renal Impairment:
Hepatic Impairment:
Pharmacology
Mechanism of Action
Pharmacokinetics
Absorption:
Distribution:
Elimination:
Pharmacodynamics
Safety & Warnings
Side Effects
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. Immediately contact your doctor or seek medical attention if you notice any of the following symptoms, which may indicate a serious allergic reaction:
- Rash
- Hives
- Itching
- Red, swollen, blistered, or peeling skin, with or without fever
- Wheezing
- Tightness in the chest or throat
- Difficulty breathing, swallowing, or talking
- Unusual hoarseness
- Swelling of the mouth, face, lips, tongue, or throat
Other Possible Side Effects
Like all medications, this drug can cause side effects, although many people may not experience any or may only have mild symptoms. If you are bothered by any of the following side effects or if they do not go away, contact your doctor or seek medical help:
- Drowsiness
- Feeling nervous and excitable
Please note that this list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult your doctor.
Reporting Side Effects
For medical advice about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe drowsiness or dizziness
- Difficulty urinating
- Blurred vision or eye pain
- Fast or irregular heartbeat
- Confusion or hallucinations
- Unusual excitement or nervousness (especially in children)
- Signs of an allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing)
Before Using This Medicine
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, any of its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
All medications you are currently taking, including prescription and over-the-counter (OTC) medications, natural products, and vitamins. This information will help your doctor and pharmacist assess potential interactions between this medication and other substances.
* Any existing health problems, as this medication may interact with certain conditions.
To ensure your safety, it is crucial to verify that it is safe to take this medication with all your current medications and health conditions. Never start, stop, or adjust the dose of any medication without first consulting your doctor.
Precautions & Cautions
Until you are familiar with how this medication affects you, exercise caution when engaging in activities that require alertness, such as driving. Additionally, avoid consuming alcohol while taking this drug, as it may interact with the medication.
Before using marijuana, other cannabis products, or any prescription or over-the-counter (OTC) medications that may cause drowsiness or impair your reactions, consult with your doctor to discuss potential risks and interactions.
When administering this medication to children, use caution, as they may be at a higher risk of experiencing excitability. If you are pregnant, planning to become pregnant, or are breast-feeding, inform your doctor, as they will need to discuss the potential benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Severe drowsiness or sedation
- Dizziness
- Ataxia (loss of coordination)
- Dry mouth and skin
- Flushing
- Dilated pupils
- Blurred vision
- Urinary retention
- Constipation
- Tachycardia (rapid heart rate)
- Hypertension (high blood pressure)
- Hyperthermia (fever)
- In severe cases: seizures, coma, respiratory depression, cardiovascular collapse.
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Management is supportive, including gastric lavage, activated charcoal, and symptomatic treatment for CNS and anticholinergic effects. Physostigmine may be considered for severe anticholinergic symptoms under medical supervision.
Drug Interactions
Major Interactions
Moderate Interactions
- Other Anticholinergic Drugs (e.g., tricyclic antidepressants, atropine, some antipsychotics): Increased risk of anticholinergic side effects (e.g., dry mouth, urinary retention, blurred vision, constipation).
- Potassium Chloride (oral forms): Increased risk of gastrointestinal lesions due to delayed gastric emptying.
Minor Interactions
- Antihypertensives: May cause additive hypotensive effects (rare).
Monitoring
Routine Monitoring
Frequency: Daily, as needed
Target: Reduction or resolution of symptoms
Action Threshold: Lack of efficacy or worsening symptoms
Frequency: Daily, especially during initial therapy
Target: Minimal or tolerable sedation
Action Threshold: Excessive drowsiness, impaired alertness, or difficulty waking
Frequency: Daily, as needed
Target: Absence or mild, tolerable effects
Action Threshold: Severe or bothersome anticholinergic symptoms
Symptom Monitoring
- Drowsiness
- Dizziness
- Dry mouth
- Blurred vision
- Urinary retention
- Constipation
- Nervousness or excitability (paradoxical reaction, especially in children)
- Nausea
- Vomiting
Special Patient Groups
Pregnancy
Triprolidine is classified as Pregnancy Category C. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Limited human data are available, but animal studies have shown some adverse effects at high doses.
Trimester-Specific Risks:
Lactation
Triprolidine is generally not recommended during breastfeeding (Lactation Risk L3 - Moderately Safe). It can be excreted into breast milk and may cause drowsiness or irritability in the infant. It may also decrease milk supply due to its anticholinergic effects.
Pediatric Use
Use with caution, especially in infants and young children, as they may be more susceptible to the sedative and anticholinergic effects. Paradoxical excitation (nervousness, restlessness, insomnia) can occur, particularly in young children. Accurate dosing using the provided dropper is crucial to prevent overdose.
Geriatric Use
Elderly patients are more susceptible to the sedative, anticholinergic, and hypotensive effects of triprolidine. Use with caution, starting with lower doses and monitoring closely for adverse effects such as confusion, dizziness, urinary retention, and constipation. Avoid use in elderly patients with cognitive impairment or benign prostatic hyperplasia.
Clinical Information
Clinical Pearls
- Triprolidine is a first-generation antihistamine known for its significant sedative and anticholinergic properties.
- Due to its sedative effects, it is often preferred for nighttime use or when drowsiness is acceptable.
- Caution is advised when combining with other CNS depressants or anticholinergic medications.
- Paradoxical excitation can occur in children, manifesting as restlessness or insomnia.
- Elderly patients are particularly vulnerable to adverse effects like confusion, urinary retention, and falls.
- Histex PD 0.938mg Drops is a specific pediatric formulation, requiring careful attention to the prescribed dose in mL.
Alternative Therapies
- Second-generation antihistamines (e.g., loratadine, cetirizine, fexofenadine) for less sedation and anticholinergic effects.
- Nasal corticosteroids (e.g., fluticasone, mometasone) for allergic rhinitis.
- Cromolyn sodium nasal spray (mast cell stabilizer).
- Saline nasal sprays for symptomatic relief.