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Azatadine Side Effects

Applies to azatadine: oral tablet.


Use caution when driving, operating machinery, or performing other hazardous activities. Azatadine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking azatadine.

Stop taking azatadine and seek emergency medical attention if you experience an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives).

Other, less serious side effects may be more likely to occur. Continue to take azatadine and talk to your doctor if you experience

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

For Healthcare Professionals

Applies to azatadine: oral tablet.

Nervous system

Nervous system side effects have commonly included central nervous system depression with resulting drowsiness. Azatadine has also caused dizziness and affected coordination.[Ref]

The drowsiness caused by azatadine may subside in some patients following prolonged use. Patients should be warned against driving, as well as concomitant ingestion of alcohol and other sedative-hypnotic drugs, while taking azatadine.

At dosages above what is normally recommended, dystonic reactions have occurred.[Ref]


Gastrointestinal side effects have included dry mouth and constipation due to anticholinergic effects. Patients have also experienced epigastric distress and nausea. Increased appetite has been reported.[Ref]


Cardiovascular side effects have included hypotension, tachycardia, and palpitations.[Ref]


Ocular side effects have included blurred vision, diplopia, and dry eyes due to cholinergic blockade.[Ref]


Genitourinary side effects have included dysuria, urinary hesitancy, decrease in urinary flow, and in rare cases, acute urinary retention. These urinary tract effects may have been due to azatadine's anticholinergic effects.[Ref]


Hematologic side effects have included reports of bone marrow suppression, thrombocytopenia, and aplastic anemia.[Ref]


Respiratory side effects have included thickening of bronchial secretions.[Ref]


Hypersensitivity reactions to azatadine have included rash and urticaria.[Ref]


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2. Azatadine (optimine)--a new antihistamine. Med Lett Drugs Ther. 1977;19:77-9.

3. Luscombe DK, Nicholls PJ, Spencer PS. Effect of azatadine on human performance. Br J Clin Pract. 1980;34:75-9.

4. Small P, Barrett D, Biskin N. Effects of azatadine, terfenadine, and astemizole on allergen-induced nasal provocation. Ann Allergy. 1990;64:129-31.

5. Joske DJ. Dystonic reaction to azatadine. Med J Aust. 1984;141:449.

6. Wilson JD, Hillas JL, Somerfield SD. Azatadine maleate (Zadine): evaluation in the management of allergic rhinitis. N Z Med J. 1981;94:79-81.

7. Kaminszczik I, Barbon L. Relieving symptoms of upper respiratory allergies and the common cold: azatadine maleate/pseudoephedrine sulfate syrup versus placebo. J Int Med Res. 1983;11:101-7.

8. Luscombe DK, Nicholls PJ, Parish PA. Comparison of the effects of azatadine maleate and terfenadine on human performance. Pharmatherapeutica. 1983;3:370-5.

9. Product Information. Optimine (azatadine). Schering Corporation. 2001.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.