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Antihistamine Medicines
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Sale 21%
Children's Zyrtec Allergy Relief Medicine Grape Flavored Syrup 8 oz
21% OFFOriginal price $ 37.85Current price $ 29.95 -
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Hydroxyzine HCL Tablets 10 mg Strength 100 Count (RX)
32% OFFOriginal price $ 13.95Current price $ 9.50 -
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Diphenhydramine Injection 50 mg/mL Benadryl Injection Vial 1 mL x 25/Tray (Rx)
25% OFFOriginal price $ 129.95Current price $ 97.00 -
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Robitussin Honey Severe Cough, Flu & Sore Throat Nighttime CF Max 4 oz
7% OFFOriginal price $ 14.00Current price $ 12.99 -
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Prednisolone Sodium Phosphate Solution 15 mg / 5 mL Grape Flavor 237 mL (RX)
5.0 (1) 5.0 out of 5 stars, 1 review32% OFFOriginal price $ 115.95Current price $ 79.00 -
Sale 26%
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Azelastine Hydrochloride 0.1% Nasal Spray by Aurobindo Pharma (RX)
26% OFFOriginal price $ 22.95Current price $ 16.95 -
Sale 34%
Olopatadine Ophthalmic Solution 0.1% Antistamine and Redness Eye Itch Relief Drops
34% OFFOriginal price $ 49.95Current price $ 32.95 -
Sale 17%
Claritin Reditabs 12 Hour Allergy Relief Melting Tablets 10mg
17% OFFOriginal price $ 18.95Current price $ 15.75 -
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Loratadine 10 mg Antihistamine Unit Dose Packets 100 Per Box
23% OFFOriginal price $ 59.95Current price $ 45.95 -
Sale 14%
Robitussin Children's Nighttime Cough DM Long-Acting Fruit Punch 4 oz.
14% OFFOriginal price $ 9.95Current price $ 8.60 -
Sale 48%
Allergy Tablets 4 Hour Relief, Antihistamine Chlorpheniramine Maleate 4 mg, 24 Count
48% OFFOriginal price $ 2.79Current price $ 1.45 -
Sale 24%
Pataday Twice Daily Eye Allergy Itch & Redness Relief Eye Drops 5 mL
24% OFFOriginal price $ 29.95Current price $ 22.89 -
Sale 16%
Mucinex Nightshift Maximum Strength All in One, Severe Cold and Flu 6 fl oz
16% OFFOriginal price $ 19.95Current price $ 16.85 -
Sale 30%
Allegra 24 Hour Allergy Relief Non-Drowsy 180 mg Tablets 15 Count
30% OFFOriginal price $ 26.95Current price $ 18.95 -
Sale 32%
Allegra Allergy 12 Hour 60 mg Tablets Non-Drowsy 12 Count
32% OFFOriginal price $ 18.95Current price $ 12.95 -
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Advil Allergy & Congestion Relief Pain Reliever/Nasal Decongestant Tablets 10 Count
31% OFFOriginal price $ 14.95Current price $ 10.25 -
Sale 35%
Allergy Nasal Spray Multi-Symptom Relief Triamcinolone Acetonide 55 mcg (glucocorticoid)
35% OFFOriginal price $ 26.95Current price $ 17.50 -
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Olopatadine Hydrochloride Nasal Spray (Nasal Solution) 665 mcg (RX)
31% OFFOriginal price $ 79.95Current price $ 54.95 -
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Clemastine Fumarate Syrup Antihistamine Oral Solution 0.5mg/5 mL, 120 mL (RX)
21% OFFOriginal price $ 499.95Current price $ 395.00 -
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Clemastine Fumarate Antihistamine Tablets 2.68 mg 100 Count (RX)
14% OFFOriginal price $ 699.00Current price $ 599.00 -
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Hydroxyzine HCL Syrup Oral Solution 10 mg/mL Alcohol Free 473 mL (RX)
25% OFFOriginal price $ 1,150.00Current price $ 859.00 -
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Hydroxyzine HCL Injection 50 mg/mL Single Dose Vial 2 mL x 25/Pack (RX)
16% OFFOriginal price $ 1,895.95Current price $ 1,585.00 -
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Hydroxyzine HCL Injection 50 mg/mL Single Dose Vial 1 mL x 25/Pack (RX)
29% OFFOriginal price $ 2,450.00Current price $ 1,750.00 -
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Hydroxyzine HCL Injection 25 mg/mL Single Dose Vial 1 mL x 25/Pack (RX)
14% OFFOriginal price $ 1,599.95Current price $ 1,375.00 -
Sale 30%
Pataday Once Daily Eye Allergy Itch & Redness Relief Eye Drops 2.5 mL
30% OFFOriginal price $ 39.95Current price $ 27.95 -
Sale 45%
Olopatadine Ophthalmic Solution 0.1% Antistamine Eye Itch Relief Drops 5 mL - Major Labs
45% OFFOriginal price $ 39.95Current price $ 22.00 -
Sale 45%
Olopatadine Ophthalmic Solution 0.2% Antistamine Eye Itch Relief Drops 2.5 mL
45% OFFOriginal price $ 39.95Current price $ 22.00
People Also Searched For
Antihistamines are medicines commonly used to relieve symptoms of allergic reactions. They work by blocking the action of histamine, a chemical your body releases during an allergy response that causes sneezing, itching, runny nose, and swelling. By preventing histamine from binding to its receptors in your body, antihistamines help reduce these symptoms and make you feel better. Most people know antihistamines as allergy pills (for hay fever, pet allergies, or hives), but they can also be used for other conditions – for example, some are taken to prevent motion sickness or treat nausea, and certain ones can even be used short-term as nighttime sleep aids. In essence, antihistamine medications turn down your body’s histamine-driven reactions, whether in the nose, skin, eyes, or elsewhere.
Primary Indications and Therapeutic Uses:
1. Allergic Disorders
- Allergic Rhinitis (Hay Fever): First-line therapy for symptomatic relief of nasal congestion, rhinorrhea, sneezing, pruritus, and conjunctivitis.
- Urticaria (Acute and Chronic Spontaneous): Core treatment to alleviate pruritus and wheal formation; second-generation agents preferred due to superior safety profile.
- Atopic Dermatitis (Adjunctive Role): Useful for dermal pruritus, particularly in cases with significant sleep disruption.
- Allergic Conjunctivitis: Oral or topical ocular antihistamines decrease histamine-mediated conjunctival symptoms.
2. Anaphylactic Reactions
- Adjunctive in Acute Management: Intravenous or intramuscular antihistamines can reduce cutaneous symptoms (e.g., urticaria, angioedema) but do not reverse airway or circulatory compromise (epinephrine remains the primary intervention).
3. Motion Sickness and Vestibular Disorders
- First-generation antihistamines (e.g., meclizine, dimenhydrinate): Possess anticholinergic and CNS-suppressant effects useful in prophylaxis and treatment of motion sickness, vertigo, and labyrinthitis.
4. Sleep Disorders (Sedative Use)
- Short-term insomnia: Some first-generation antihistamines (e.g., diphenhydramine, doxylamine) are used off-label for their sedating properties but are not recommended for long-term management due to anticholinergic burden and cognitive impairment risk, especially in older adults.
5. Cough, Cold, and Respiratory Illnesses
- Component of many combination remedies for cough and upper respiratory symptoms, although efficacy for viral infections is limited and use in young children is discouraged due to safety concerns.
Other and Emerging Indications
- Antiemetic therapy: In chemotherapy- or pregnancy-induced nausea and vomiting (e.g., promethazine).
- Adjunctive analgesia: In combination with opioids to manage opioid-induced pruritus.
- Part of multi-modal regimens in mast cell activation disorders/neoplasms (e.g., systemic mastocytosis).
Classification and Considerations
- First-generation antihistamines: Cross the blood-brain barrier, leading to sedation and anticholinergic effects (dry mouth, urinary retention, delirium).
- Second- and Third-generation antihistamines: More selective and less sedating (loratadine, cetirizine, fexofenadine, levocetirizine, desloratadine), preferred for chronic use.
Safety and Contraindications
- Adverse effects: Include sedation, cognitive impairment, anticholinergic side effects (first-generation), paradoxical agitation in children, QT prolongation in susceptible individuals.
- Drug interactions: May potentiate CNS depressants and other anticholinergic medications; caution in elderly, patients with glaucoma, benign prostatic hyperplasia, or cardiac arrhythmias.
Antihistamine medicines are critical agents in the management of a broad spectrum of allergic disorders, urticaria, certain pruritic skin conditions, motion sickness, and serve as adjuncts in anaphylaxis and other rare indications. Their utility is governed by their generation-specific pharmacodynamics, safety profile, and patient-specific factors. Judicious selection and dosing are essential to maximize efficacy and minimize adverse outcomes.










