Histabloc

Histabloc competes with free histamine for binding at HA-receptor sites. This antagonizes the effects of histamine on HA-receptors, leading to a reduction of the negative symptoms brought on by histamine HA-receptor binding. In addition to the usual allergic symptoms, the drug also treats irritant cough and nausea, vomiting, and vertigo associated with motion sickness. Histabloc's anticholinergic action appears to be due to a central antimuscarinic effect, which also may be responsible for its antiemetic effects, although the exact mechanism is unknown. It also is used commonly to treat drug-induced extrapyramidal symptoms as well as to treat mild cases of Parkinson's disease.

Treatment of seasonal allergic rhinitis, perennial rhinitis, urticaria, allergic dermatologic disorders, angioedema and conjunctivitis. Histabloc is generally considered to be ineffective in asthma.

Acute anaphylaxis should be treated with adrenaline; Histabloc and corticosteroids are given to prevent relapse.

Histabloc is also used to control the pruritus associated with skin disorders eg, atopic eczema.

Histabloc is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.

Histabloc is used to treat sneezing, runny nose, watery eyes, hives, skin rash, itching, and other cold or allergy symptoms.

Histabloc is also used to treat skin hives and itching in people with chronic skin reactions.

Histabloc may also be used for purposes not listed in this medication guide.

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Capsule,

Oral:

Histabloc: 10 mg [contains brilliant blue fcf (fd&c blue #1)]

GoodSense Allergy Relief: 10 mg [contains brilliant blue fcf (fd&c blue #1)]

Generic: 10 mg

Solution,

Oral:

Childrens Histabloc: 5 mg/5 mL (120 mL) [alcohol free, dye free, sugar free; contains propylene glycol, sodium benzoate; grape flavor]

Histabloc Childrens: 5 mg/5 mL (120 mL [DSC]) [alcohol free, dye free, sugar free; contains polyethylene glycol, propylene glycol, sodium benzoate; grape flavor]

Histabloc Childrens: 5 mg/5 mL (120 mL [DSC]) [alcohol free, dye free, sugar free; contains propylene glycol, sodium benzoate; fruit flavor]

Histabloc Hives Relief: 5 mg/5 mL (120 mL [DSC]) [alcohol free, dye free, sugar free; contains propylene glycol, sodium benzoate; grape flavor]

Syrup,

Oral:

Childrens Histabloc: 5 mg/5 mL (120 mL) [fruit flavor]

Childrens Histabloc: 5 mg/5 mL (120 mL) [alcohol free, dye free; contains propylene glycol, sodium benzoate, sodium metabisulfite; grape flavor]

Histabloc: 5 mg/5 mL (60 mL [DSC], 120 mL [DSC], 150 mL [DSC]) [alcohol free, color free, dye free, sugar free; contains edetate disodium, propylene glycol, sodium benzoate; grape flavor]

Histabloc Allergy Childrens: 5 mg/5 mL (240 mL) [alcohol free, dye free, sugar free; contains edetate disodium, propylene glycol, sodium benzoate, sorbitol]

Histabloc Childrens: 5 mg/5 mL (120 mL) [alcohol free, dye free, gluten free, sugar free; contains edetate disodium, propylene glycol, sodium benzoate; grape flavor]

Histabloc Childrens: 5 mg/5 mL (10 mL) [alcohol free, dye free, sugar free; contains propylene glycol, sodium benzoate; grape flavor]

Histabloc Childrens: 5 mg/5 mL (120 mL) [sugar free; contains polyethylene glycol, propylene glycol, sodium benzoate, sodium metabisulfite; grape flavor]

Generic: 5 mg/5 mL (120 mL)

Tablet,

Oral:

Allergy: 10 mg [DSC]

Allergy Non-Drowsy: 10 mg [DSC]

Allergy Relief: 10 mg

Allergy Relief: 10 mg [contains corn starch]

Allergy Relief: 10 mg [gluten free]

Allergy Relief Histabloc: 10 mg

Histabloc: 10 mg

Loradamed: 10 mg

Generic: 10 mg

Tablet Chewable,

Oral:

Histabloc: 5 mg [contains aspartame, fd&c blue #2 aluminum lake; grape flavor]

Histabloc Childrens: 5 mg [contains aspartame]

Histabloc Childrens: 5 mg [DSC] [contains aspartame; bubble-gum flavor]

Tablet Disintegrating,

Oral:

Histabloc: 10 mg [contains aspartame]

Histabloc: 10 mg [contains aspartame; citrus flavor]

Allergy Relief: 10 mg [DSC] [contains aspartame]

Histabloc Reditabs: 5 mg, 10 mg

Triaminic Allerchews: 10 mg

Dosing: Adult

Allergic rhinitis or conjunctivitis:

Oral: 10 mg once daily or 5 mg twice daily.

OTC labeling (patient-guided therapy for symptoms of hay fever or other upper respiratory allergies):

Oral: 10 mg once daily or 5 mg twice daily; maximum dose: 10 mg/day.

Urticaria (acute and chronic spontaneous):

Oral: Initial: 10 mg once daily. If symptom control is inadequate, may increase to 10 mg twice daily. There is limited evidence for larger doses. Reevaluate necessity for continued treatment periodically (Asero 2020; Khan 2019; Zuberbier 2018).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Allergic symptoms/rhinitis:

Oral

Children 2 to <6 years:

Oral liquid or chewable tablet: 5 mg once daily

Children ≥6 years and Adolescents:

Oral liquid, capsule, tablet, or chewable tablet: 10 mg once daily

Dispersible tablet: 5 mg twice daily or 10 mg once daily

Chronic idiopathic urticaria: Limited data available (Kliegman 2011; Simons 1994):

Children 2 to 12 years: 5 mg once daily

Adolescents: 10 mg once daily

See also:
What is the most important information I should know about Histabloc?

You should not take this medication if you are allergic to Histabloc or to desloratadine (Clarinex).

Ask a doctor or pharmacist before taking this medicine if you have liver or kidney disease.

Do not give this medication to a child younger than 6 years old without the advice of a doctor.

Histabloc disintegrating tablets (Histabloc Reditab) may contain phenylalanine. Talk to your doctor before using this form of Histabloc if you have phenylketonuria (PKU).

Use Histabloc orally disintegrating tablets as directed by your doctor. Check the label on the medicine for exact dosing instructions.

• Take Histabloc orally disintegrating tablets by mouth with or without food.
• Be sure that your hands are completely dry before you handle Histabloc orally disintegrating tablets. Use the tablet right away after you remove it from the tablet blister.
• To open the tablet blister, peel back the foil, then gently remove the tablet. Place the tablet on the tongue. The tablet will dissolve quickly. You may take Histabloc orally disintegrating tablets with or without water.
• If you miss a dose of Histabloc orally disintegrating tablets, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Histabloc orally disintegrating tablets.

This medication is an antihistamine that treats symptoms such as itching, runny nose, watery eyes, and sneezing from "hay fever" and other allergies. It is also used to relieve itching from hives.

Histabloc does not prevent hives or prevent/treat a serious allergic reaction (e.g., anaphylaxis). Therefore, if your doctor has prescribed epinephrine to treat allergic reactions, always carry your epinephrine injector with you. Do not use Histabloc in place of your epinephrine.

If you are self-treating with this medication, it is important to read the manufacturer's package instructions carefully so you know when to consult your doctor or pharmacist.

Do not use this medication in children younger than 6 years unless directed by the doctor.

How to use Histabloc

If you are using the over-the-counter product to self-treat, read all the directions on the product package before taking this medication. If your doctor has prescribed this medication, follow your doctor's directions and the instructions on your prescription label. If you have any questions, consult your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor or the product package, usually once or twice a day. Remove the tablet from its foil pack immediately before taking and place the tablet on the tongue. It will dissolve quickly. You may swallow the dissolved medication with or without water. Dosage is based on your age, condition, and response to treatment. Do not increase your dose or take this drug more often than directed. Do not take more of this medication than recommended for your age.

Tell your doctor if your allergy symptoms do not improve after 3 days of treatment or if your hives last more than 6 weeks. Seek immediate medical attention if your condition worsens or you think you have a serious medical problem (e.g., very serious allergic reaction/anaphylaxis).

See also:
What other drugs will affect Histabloc?

Histabloc (10 mg once daily) has been coadministered with therapeutic doses of erythromycin, cimetidine, and ketoconazole in controlled clinical pharmacology studies in adult volunteers. Although increased plasma concentrations (AUC 0-24 hrs) of Histabloc and/or descarboethoxyloratadine were observed following coadministration of Histabloc with each of these drugs in normal volunteers (n = 24 in each study), there were no clinically relevant changes in the safety profile of Histabloc, as assessed by electrocardiographic parameters, clinical laboratory tests, vital signs, and adverse events. There were no significant effects on QT_c intervals, and no reports of sedation or syncope. No effects on plasma concentrations of cimetidine or ketoconazole were observed. Plasma concentrations (AUC 0-24 hrs) of erythromycin decreased 15% with coadministration of Histabloc relative to that observed with erythromycin alone. The clinical relevance of this difference is unknown. These above findings are summarized in TABLE 1.

See also:
What are the possible side effects of Histabloc?

Applies to Histabloc: oral fixed-combination tablets, oral orally disintegrating tablets, oral solution, oral tablets

Side effects include:

Children 2–5 years of age receiving oral solution: Diarrhea, epistaxis, pharyngitis, flu-like symptoms, fatigue, stomatitis, tooth disorder, earache, viral infection, rash.

Children 6–12 years of age receiving oral solution: Nervousness, wheezing, fatigue, hyperkinesia, abdominal pain, conjunctivitis, dysphonia, upper respiratory tract infection.

Adults and children ≥12 years of age receiving conventional or orally disintegrating tablets: Headache, somnolence, fatigue, dry mouth.

Fixed combination Histabloc (the active ingredient contained in Histabloc Reditab) pseudoephedrine sulfate preparations: Insomnia, dry mouth, headache, somnolence, nervousness, dizziness, fatigue.