Living with Advanced MS? Watch this video to learn more.

Meclizine (Systemic)



INN:

Meclozine {09}

BAN:
Meclozine {09}

VA CLASSIFICATION
Primary: GA609
Secondary: CN550

Commonly used brand name(s): Antivert; Antivert/25; Antivert/50; Bonamine; Bonine; Dramamine II; Meclicot; Medivert.

Note: For a listing of dosage forms and brand names by country availability, see Dosage Forms section(s).



Category:


Antiemetic—

antivertigo agent—

Indications

Note: Bracketed information in the Indications section refers to uses that are not included in U.S. product labeling.

Accepted

Motion sickness (prophylaxis and treatment)—Meclizine is indicated for the prophylaxis and treatment of nausea, vomiting, and dizziness associated with motion sickness {01} {02} {07} {08} {10} {11}.

Vertigo (prophylaxis and treatment)—The U.S. Food and Drug Administration (FDA) has classified meclizine as possibly effective in the management of vertigo associated with diseases affecting the vestibular system, {01} {07} {10} such as labyrinthitis and Meniere's disease. {10} {11} This classification requires the submission of adequate and well-controlled studies to provide substantial evidence of effectiveness. {01} {07}

[Nausea and vomiting, radiotherapy-induced (prophylaxis and treatment)]—Meclizine is indicated for the prophylaxis and treatment of nausea, vomiting, and dizziness associated with radiotherapy. {10}


Pharmacology/Pharmacokinetics

Physicochemical characteristics:
Molecular weight—
    481.90 {09}

Mechanism of action/Effect:

Antiemetic; antivertigo agent—The mechanism by which meclizine exerts its antiemetic, anti–motion sickness, and antivertigo effects is not precisely known but may be related to its central anticholinergic actions. It diminishes vestibular stimulation and depresses labyrinthine function. {02} {04} An action on the medullary chemoreceptive trigger zone may also be involved in the antiemetic effect.


Other actions/effects:

Meclizine also has antihistaminic {04} {11}, anticholinergic {04} {10}, and central nervous system (CNS) depressant {04} {11} effects.

Half-life:

6 hours. {04}

Onset of action:

1 hour. {04}

Duration of action:

8 to 24 hours. {04} {11}


Precautions to Consider

Pregnancy/Reproduction

Pregnancy—
Epidemiological studies in pregnant women have not shown that meclizine causes an increase in the risk of fetal abnormalities. {07} {10}

Studies in rats have shown that meclizine causes cleft palate when given in doses corresponding to 25 to 50 times the recommended human dose. {01} {07} {10}

FDA Pregnancy Category B. {01} {07}

Breast-feeding

Meclizine may be distributed into breast milk. However, problems in humans have not been documented.

Because of its anticholinergic actions, meclizine may inhibit lactation.

Pediatrics

No information is available on the relationship of age to the effects of meclizine in pediatric patients. {07} {08} However, it is known that pediatric patients exhibit increased sensitivity to anticholinergic agents, which are related pharmacologically to meclizine.


Geriatrics


No information is available on the relationship of age to the effects of meclizine in geriatric patients. However, it is known that geriatric patients exhibit increased sensitivity to anticholinergic agents, {03} which are related pharmacologically to meclizine. Therefore, constipation, dryness of mouth, and urinary retention (especially in males) are more likely to occur in the elderly.


Dental

Prolonged use of meclizine may decrease or inhibit salivary flow, thus contributing to the development of caries, periodontal disease, oral candidiasis, and discomfort. {14}

Drug interactions and/or related problems
The following drug interactions and/or related problems have been selected on the basis of their potential clinical significance (possible mechanism in parentheses where appropriate)—not necessarily inclusive (» = major clinical significance):


Note: Combinations containing any of the following medications, depending on the amount present, may also interact with this medication.

» Alcohol{01}{02}{07}{08}{10} or
» CNS depression–producing medications, other{02}{04}{08}{10} (see Appendix II )    (concurrent use may potentiate the CNS depressant effects of either these medications or meclizine)


Anticholinergics or other medications with anticholinergic activity{04}{06} (see Appendix II )    (concurrent use with meclizine may potentiate anticholinergic effects)


Apomorphine{05}    (prior administration of meclizine may decrease the emetic response to apomorphine)



Laboratory value alterations
The following have been selected on the basis of their potential clinical significance (possible effect in parentheses where appropriate)—not necessarily inclusive (» = major clinical significance):

With diagnostic test results
Skin tests using allergen extracts{04}    (may inhibit the cutaneous histamine response, thus producing false-negative results; it is recommended that meclizine be discontinued at least 72 hours before testing begins)


Medical considerations/Contraindications
The medical considerations/contraindications included have been selected on the basis of their potential clinical significance (reasons given in parentheses where appropriate)— not necessarily inclusive (» = major clinical significance).


Risk-benefit should be considered when the following medical problems exist
Bladder neck obstruction or
Prostatic hyperplasia, symptomatic{01}{07}{08}{10}    (anticholinergic effects of meclizine may precipitate urinary retention)


Gastroduodenal obstruction    (decrease in motility and tone may occur, aggravating obstruction and gastric retention)


Glaucoma, angle-closure, predisposition to{01}{07}{08}{10}    (increased intraocular pressure may precipitate an acute attack of angle-closure glaucoma)


Pulmonary disease, chronic obstructive{02}{07}{08}    (reduction in bronchial secretion may cause inspissation and formation of bronchial plugs {12})


Sensitivity to meclizine{07}{10}


Side/Adverse Effects
The following side/adverse effects have been selected on the basis of their potential clinical significance (possible signs and symptoms in parentheses where appropriate)—not necessarily inclusive:

Those indicating need for medical attention only if they continue or are bothersome
Incidence more frequent
    
Drowsiness{01}{02}{07}{08}{10}

Incidence less frequent or rare
    
Blurred vision{01}{07}{08}{10}
    
dryness of mouth{01}{07}{08}{10} , nose{01} , and throat{01}





Overdose
For specific information on the agents used in the management of meclizine overdose, see:    • Charcoal, Activated (Oral-Local) monograph;
   • Diazepam in Benzodiazepines (Systemic) monograph;
   • Ipecac (Oral-Local) monograph;
   • Norepinephrine and/or Phenylephrine in Sympathomimetic Agents—Cardiovascular Use (Parenteral-Systemic) monograph;
   • Physostigmine (Systemic)monograph.


For more information on the management of overdose or unintentional ingestion, contact a Poison Control Center (see Poison Control Center Listing ).

Clinical effects of overdose
The following effects have been selected on the basis of their potential clinical significance (possible signs and symptoms in paretheses where appropriate)—not necessarily inclusive:
    
CNS depression, including drowsiness and coma{13}
    
hypotension{13} —especially in the elderly{13}
    
anticholinergic effects{13} , including blurred vision, constipation, or dryness of mouth, nose, or throat —especially in children{13}
    
CNS stimulation{13} , including hallucinations, insomnia (trouble in sleeping), and seizures —especially in children{13}


Treatment of overdose
There is no specific antidote for meclizine overdose {13}. Treatment is primarily symptomatic and supportive {13}.

To decrease absorption—If ingestion is recent (i.e., within 1 hour), induce emesis with syrup of ipecac or perform gastric lavage {13}. Activated charcoal may be used {13}.

Specific treatment—Hypotension may be corrected with vasopressors such as norepinephrine or phenylephrine; epinephrine should not be used because it may lower blood pressure further {13}. Physostigmine may be used to counteract the anticholinergic effects {13}. Intravenous diazepam may be used to treat seizures that do not respond to physostigmine {13}.

Supportive care—The patient should be kept calm to minimize excitement {13}. Patients in whom intentional overdose is confirmed or suspected should be referred for psychiatric consultation.


Patient Consultation
As an aid to patient consultation, refer to Advice for the Patient, Meclizine/Buclizine/Cyclizine (Systemic) .

In providing consultation, consider emphasizing the following selected information (» = major clinical significance):

Before using this medication
»   Conditions affecting use, especially:
Sensitivity to meclizine

Pregnancy—No increase in fetal abnormalities in human studies; animal studies have shown meclizine to cause cleft palate at doses above recommended human dose





Breast-feeding—May be distributed into breast milk; may inhibit lactation due to anticholinergic effects





Use in children—Possible increased susceptibility to anticholinergic side effects






Use in the elderly—Possible increased susceptibility to anticholinergic side effects
Other medications, especially alcohol and other CNS depressants

Proper use of this medication
Not taking more medication than the amount recommended {02}

» Proper dosing
Missed dose (if on a regular dosing regimen): Taking as soon as possible; not taking if almost time for next dose; not doubling doses

» Proper storage

Precautions while using this medication
Possible interference with skin tests using allergens; need to inform physician of use of this medication

» Avoiding use of alcohol or other CNS depressants

» Caution if drowsiness occurs

Possible dryness of mouth; using sugarless candy or gum, ice, or saliva substitute for relief; checking with physician or dentist if dry mouth continues for more than 2 weeks


General Dosing Information
For prophylaxis of motion sickness, this medication should be taken at least 1 hour before exposure to conditions that may precipitate motion sickness. {01} {02} {07} {08} {10} {11}


Oral Dosage Forms

Note: Bracketed uses in the Dosage Forms section refer to categories of use and/or indications that are not included in U.S. product labeling.

MECLIZINE HYDROCHLORIDE CAPSULES

Usual adult and adolescent dose
Motion sickness (prophylaxis and treatment)—Oral, 25 to 50 mg one hour before travel. Dose may be repeated every twenty-four hours as needed. {01} {07} {08} {10}

Vertigo (prophylaxis and treatment)—Oral, 25 to 100 mg a day as needed, in divided doses. {01} {07} {10}

[Nausea and vomiting, radiotherapy-induced (prophylaxis and treatment)]—Oral, 50 mg two to twelve hours prior to radiotherapy. {10} {12}

Usual pediatric dose
Antiemetic or
Antivertigo agent
Children up to 12 years of age: Use is not recommended unless directed by a physician. {02} {07} {08}

Children 12 years of age or older: See Usual adult and adolescent dose.


Usual geriatric dose
See Usual adult and adolescent dose .

Note: Geriatric patients may be more sensitive to the effects of the usual adult dose.


Strength(s) usually available
U.S.—
Not commercially available.

Canada—
Not commercially available.

Packaging and storage:
Store below 40 °C (104 °F), preferably between 15 and 30 °C (59 and 86 °F), in a well-closed container, unless otherwise specified by manufacturer.

Auxiliary labeling:
   • May cause drowsiness.
   • Avoid alcoholic beverages.


MECLIZINE HYDROCHLORIDE TABLETS USP

Usual adult and adolescent dose
See Meclizine Hydrochloride Capsules.

Usual pediatric dose
See Meclizine Hydrochloride Capsules.

Usual geriatric dose
See Meclizine Hydrochloride Capsules.

Strength(s) usually available
U.S.—


12.5 mg (Rx) [Antivert] [Meclicot][Generic]


25 mg [Antivert/25 (Rx)] [Dramamine II (OTC)] [Meclicot (Rx)][Generic]


30 mg (Rx) [Medivert]


50 mg (Rx) [Antivert/50 (scored)][Generic]

Canada—
Not commercially available.

Packaging and storage:
Store below 40 °C (104 °F), preferably between 15 and 30 °C (59 and 86 °F), unless otherwise specified by manufacturer. Store in a well-closed container.

Auxiliary labeling:
   • May cause drowsiness.
   • Avoid alcoholic beverages.


MECLIZINE HYDROCHLORIDE TABLETS (CHEWABLE) USP

Usual adult and adolescent dose
See Meclizine Hydrochloride Capsules.

Usual pediatric dose
See Meclizine Hydrochloride Capsules.

Usual geriatric dose
See Meclizine Hydrochloride Capsules.

Strength(s) usually available
U.S.—


25 mg [Bonine (OTC)][Generic]

Canada—


25 mg (Rx) [Bonamine (scored; fruit-flavored)]

Packaging and storage:
Store between 15 and 30 °C (59 and 86 °F), {10} unless otherwise specified by manufacturer. Store in a well-closed container.

Auxiliary labeling:
   • May cause drowsiness.
   • Avoid alcoholic beverages.
   • May be chewed, swallowed whole, or allowed to dissolve in the mouth. {08} {10} {13}



Revised: 02/24/1999



References
  1. Antivert package insert (Roerig—US), Rev 12/81, Rec 1988.
  1. Dramamine II package label (Upjohn—US), Rec 8/7/95.
  1. Knoben J, Anderson P. Handbook of clinical drug data. 6th ed. Hamilton, IL: Drug Intelligence Publications.
  1. Deglin JH, Vallerand AH. Davis's drug guide for nurses. 4th ed. Philadelphia, PA: F.A. Davis Company; 1995. p. 693-4.
  1. Marezine injection package insert (Cyclizine, Burroughs Wellcome—US), Rev 5/89, Rec 11/89.
  1. McInnes G, Brodie M. Drug interactions that matter. Drugs 1988; 36: 83-110.
  1. Antivert (Pfizer). In: PDR Physicians' desk reference. 49th ed. 1995. Montvale, NJ: Medical Economics Data; 1995. p. 2080.
  1. Bonine (Pfizer). In: PDR Physicians' desk reference. 49th ed. 1995. Montvale, NJ: Medical Economics Data; 1995. p. 1869.
  1. Canada JR, editor. USP dictionary of USAN and international drug names 1998. Rockville, MD: The United States Pharmacopeial Convention Inc; 1997. p. 443.
  1. Bonamine (Pfizer). In: Krogh CME, editor. CPS Compendium of pharmaceuticals and specialties. 30th ed. Ottawa: Canadian Pharmaceutical Association; 1995. p. 180.
  1. Reynolds JEF, editor. Martindale: the extra pharmacopeia. 30th ed. London: The Pharmaceutical Press; 1993. p. 941.
  1. Reviewers' consensus on monograph revision of 10/95.
  1. Bonamine (Pfizer). In: Gillis MC, editor. CPS Compendium of pharmaceuticals and specialties. 33rd ed. Ottawa: Canadian Pharmacists Association; 1998. p. 215-6.
  1. Dentistry Advisory Panel, 1987–1988.
Hide
(web4)