When administered concomitantly with alcohol, loratadine has no potentiating effect as measured by psychomotor performance studies.

When sympathomimetic drugs are given to patients receiving MAO inhibitors, hypertensive reactions, including hypertensive crises, may occur. The antihypertensive effects of methyldopa, mecamylamine, reserpine and veratrum alkaloids may be reduced by sympathomimetics. Beta-adrenergic blocking agents may also interact with sympathomimetics. Increased ectopic pacemaker activity can occur when pseudoephedrine sulfate is used concomitantly with digitalis. Antacids increase the rate of pseudoephedrine sulfate absorption; kaolin decreases it. The antibacterial agent, furazolidone, is known to cause a dose-related inhibition of MAO. Although there are no reports of a hypertensive crisis caused by the concurrent administration of pseudoephedrine and furazolidone, they should not be taken together. Care should be taken in the administration of Claritin Allergy & Sinus concomitantly with other sympathomimetic amines because the combined effects on the cardiovascular system may be harmful to the patient.

Increases in plasma concentrations of loratadine have been reported after concomitant use with ketoconazole, erythromycin or cimetidine in controlled clinical trials, but without clinically significant changes (including electrocardiographic). Other drugs known to inhibit hepatic metabolism should be coadministered with caution until definitive interaction studies can be completed.

During controlled clinical studies with the recommended dosage, the incidence of adverse effects associated with Claritin Allergy & Sinus was comparable to that of placebo, with the exception of insomnia and dry mouth both of which were commonly reported. Other most frequently reported [≥5%] adverse reactions associated with Claritin Allergy & Sinus, the components and placebo are listed in Table 1.

Rare adverse reactions in decreasing order of frequency included, nausea, abdominal distress, anorexia, thirst, tachycardia, pharyngitis, rhinitis, acne, pruritus, rash, urticaria, arthralgia, confusion, dysphonia, hyperkinesia, hypoesthesia, decreased libido, paresthesia, tremor, vertigo, flushing, postural hypotension, increased sweating, eye disorders, earache, tinnitus, taste abnormality, agitation, apathy, depression, euphoria, paroniria, increased appetite, change in bowel habits, dyspepsia, eructation, hemorrhoids, tongue discoloration, tongue disorder, vomiting, transient abnormal hepatic function, dehydration, increased weight, hypertension, palpitation, migraine, bronchospasm, coughing, dyspnea, epistaxis, nasal congestion, sneezing, nasal irritation, dysuria, micturition disorder, nocturia, polyuria, urinary retention, asthenia, back pain, leg cramps, malaise and rigors.

As with other sympathomimetic amines, CNS stimulation, muscular weakness, tightness in the chest and syncope may also be encountered.

During the marketing of loratadine, alopecia, anaphylaxis and abnormal hepatic function have been reported rarely.

Table 1: Claritin Allergy & Sinus

Number (%) of Patients Reporting Adverse Experiences (Probably or Possibly Related to Treatment) ≥5% Incidence During Treatment with Claritin Allergy & Sinus, Either Component Alone (Loratadine or Pseudoephedrine) or Placebo in Clinical Studies