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Help I Have Allergies Side Effects

Generic Name: loratadine

Note: This page contains information about the side effects of loratadine. Some of the dosage forms included on this document may not apply to the brand name Help I Have Allergies.

For the Consumer

Applies to loratadine: 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 loratadine (the active ingredient contained in Help I Have Allergies) pseudoephedrine sulfate preparations: Insomnia, dry mouth, headache, somnolence, nervousness, dizziness, fatigue.

For Healthcare Professionals

Applies to loratadine: oral capsule, oral syrup, oral tablet, oral tablet chewable, oral tablet disintegrating

Nervous system

Nervous system side effects have included headache in approximately 7% of treated patients. Usually, loratadine (the active ingredient contained in Help I Have Allergies) has not been shown to cause significant drowsiness, sedation, or impair psychomotor skills.[Ref]

One study of second generation antihistamines reported cetirizine was 3.5 times more likely and acrivastine 2.8 times more likely to result in sedation than loratadine. There was no significant difference in incidence of sedation between loratadine and fexofenadine.[Ref]


One study reported prolongation of the QT interval when larger than recommended (20 mg per day) doses of loratadine (the active ingredient contained in Help I Have Allergies) were administered with nefazodone (300 mg every 12 hours).[Ref]

Cardiovascular side effects have included hypertension, hypotension, palpitation, supraventricular tachyarrhythmias, syncope and tachycardia.[Ref]


Gastrointestinal side effects have included rare reports of nausea and dry mouth.[Ref]


Hepatic side effects have included rare reports of jaundice, hepatitis, and hepatic necrosis.[Ref]

Two cases of necroinflammatory liver injury have been reported in patients taking loratadine. One case presented within 2 weeks of starting loratadine therapy and the other occurred 14 months after the start of therapy. Liver transplantation was necessary in one patient.[Ref]


Dermatologic side effects have included a case report of a fixed drug eruption.[Ref]


1. "Product Information. Claritin (loratadine)." Schering Laboratories, Kenilworth, NJ.

2. Simons FER, Fraser TG, Reggin JD, Simons KJ "Comparison of the central nervous system effects produced by six h-1-receptor antagonists." Clin Exp Allergy 26 (1996): 1092-7

3. Monroe EW "Loratadine in the treatment of urticaria." Clin Ther 19 (1997): 232-42

4. Monroe EW, Bernstein DI, Fox RW, Grabiec SV, Honsinger RW, Kalivas JT, Katz HI, Cuss F, Danzig MR, Garvin PR, et al "Relative efficacy and safety of loratadine, hydroxyzine, and placebo in chronic idiopathic urticaria." Arzneimittelforschung 42 (1992): 1119-21

5. Clissold SP, Sorkin EM, Goa KL "Loratadine. A preliminary review of its pharmacodynamic properties and therapeutic efficacy." Drugs 37 (1989): 42-57

6. Monroe EW "Safety and efficacy of loratadine in urticaria." Int J Dermatol 35 (1996): 837-41

7. Kay GG, Berman B, Mockoviak SH, Morris CE, Reeves D, Starbuck V, Sukenik E, Harris AG "Initial and steady-state effects of diphenhydramine and loratadine on sedation, cognition, mood, and psychomotor performance." Arch Intern Med 157 (1997): 2350-6

8. Mann RD, Pearce GL, Dunn N, Shakir S "Sedation with ''non-sedating'' antihistamines: four prescription-event monitoring studies in general practice." Br Med J 320 (2000): 1184-6

9. Bender BG, McCormick DR, Milgrom H "Children's school performance is not impaired by short-term administration of diphenhydramine or loratadine." J Pediat 138 (2001): 656-60

10. Adelsberg BR "Sedation and performance issues in the treatment of allergic conditions." Arch Intern Med 157 (1997): 494-500

11. Ducic I, Ko CM, Shuba Y, Morad M "Comparative effects of loratadine and terfenadine on cardiac K+ channels." J Cardiovasc Pharmacol 30 (1997): 42-54

12. Smith SJ "Cardiovascular toxicity of antihistamines." Otolaryngol Head Neck Surg 111 Suppl (1994): 348-54

13. Abernethy DR, Barbey JT, Franc J, Brown KS, Feirrera I, Ford N, Salazar DE "Loratadine and terfenadine interaction with nefazodone: Both antihistamines are associated with QTc prolongation." Clin Pharmacol Ther 69 (2001): 96-103

14. Delgado LF, Pferferman A, Sole D, Naspitz CK "Evaluation of the potential cardiotoxicity of the antihistamines terfenadine, astemizole, loratadine, and cetirizine in atopic children." Ann Allergy Asthma Immunol 80 (1998): 333-7

15. Rankin AC "Non-sedating antihistamines and cardiac arrhythmia." Lancet 350 (1997): 1115-6

16. Good AP, Rockwood R, Schad P "Loratadine and ventricular tachycardia." Am J Cardiol 74 (1994): 207

17. Woosley RL "Cardiac actions of antihistamines." Annu Rev Pharmacol Toxicol 36 (1996): 233-52

18. Carr RA, Edmonds A, Shi H, Locke CS, Gustavson LE, Craft JC, Harris SI, Palmer R "Steady-state pharmacokinetics and electrocardiographic pharmacodynamics of clarithromycin and loratadine after individual or concomitant administration." Antimicrob Agents Chemother 42 (1998): 1176-80

19. Mayers DJ, Hindmarsh KW, Sankaran K, et al "Chloral hydrate disposition following single-dose administration to critically ill neonates and children." Dev Pharmacol Ther 16 (1991): 71-7

20. Schiano TD, Bellary SV, Cassidy MJ, Thomas RM, Black M "Subfulminant liver failure and severe hepatotoxicity caused by loratadine use." Ann Intern Med 125 (1996): 738-40

21. Ruiz-Genao DP, Hernandez-Nunez A, Sanchez-Perez J, Garcia-Diez A "Fixed drug eruption due to loratadine." Br J Dermatol 146 (2002): 528-9

Not all side effects for Help I Have Allergies may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

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