Loratadine side effects
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Common Loratadine Side Effects
Loratadine is generally well tolerated and is considered a non-sedating antihistamine. The most commonly reported side effects at the standard dose of 10 mg daily include headache, fatigue, and somnolence (drowsiness), but these occur at rates similar to or only slightly higher than placebo. Dry mouth is also occasionally reported as a side effect, but it is less common compared to some other antihistamines Haria1994Al-Assady2021Yamprasert2020+1 MORE.
Comparison to Other Antihistamines: Sedation and Anticholinergic Effects
Compared to first-generation antihistamines, loratadine causes much less drowsiness, altered mood, or impairment of cognitive and psychomotor performance. Studies show that the incidence of sedation with loratadine is similar to placebo and significantly lower than with older antihistamines like clemastine, azatadine, and chlorpheniramine. Loratadine also has a low rate of anticholinergic side effects (such as dry mouth or constipation), again comparable to placebo Haria1994Belaich1990Rj1987+1 MORE.
Central Nervous System (CNS) Effects
Loratadine does not significantly affect the central nervous system. Research using self-report measures and physiological tests (like EEG and sleep latency) found that loratadine does not cause drowsiness, mood changes, or impair driving, memory, or attention, unlike first-generation antihistamines .
Serious and Rare Side Effects
Serious side effects, such as dangerous heart rhythm problems (ventricular arrhythmias), have not been observed with loratadine, unlike some other second-generation antihistamines .
Side Effects in Special Populations
In studies involving pregnant women, loratadine did not increase the risk of birth defects, miscarriage, or affect birth weight and gestational age, suggesting it is relatively safe in pregnancy, though more research is needed .
Loratadine and Sexual Dysfunction
There are some reports that loratadine may help reverse sexual dysfunction caused by certain antidepressants (SSRIs), with only mild side effects like dry mouth and sedation, which were manageable by adjusting the dose or timing Brubaker2002Pess2002.
Alternative Treatments and Side Effect Comparison
When compared to herbal alternatives like ginger extract for allergic rhinitis, loratadine was found to have similar effectiveness, but ginger caused even fewer side effects, especially less drowsiness, fatigue, dizziness, and constipation .
Conclusion
Loratadine is a well-tolerated, non-sedating antihistamine with a low risk of side effects. The most common side effects are mild and include headache, fatigue, drowsiness, and dry mouth, but these are generally no more frequent than with placebo. Serious side effects are rare, and loratadine is considered safer than many older antihistamines, especially regarding sedation and anticholinergic effects.
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