Inclusion Criteria:

• Healthy male or non-pregnant, non-lactating female subjects; 12-55 years of age; within 15% of normal body weight for their height or had a body mass index (BMI) less than 29.9 kg/m2; positive histamine skin prick tests (or a duplicate histamine skin prick test) of summation flare > 20 mm larger than diluent control, and summation wheal > 6 mm larger than diluent control at the screening Visit 1.

Exclusion Criteria:

• Asthma that required treatment with medication other than an inhaled, short-acting beta agonist
• Signs and symptoms of currently active allergic disease (SAR, perennial allergic rhinitis, episodic allergic rhinitis)
• Upper respiratory tract infection, sinusitis, asthma or flu-like symptoms within 2 weeks prior to Visit 1
• Dermatographism or other skin conditions that might interfere with the interpretation of the skin test results
• Treatment with escalating doses of immunotherapy, oral immunotherapy, or short course (rush) immunotherapy
• Any excessive amounts of alcohol (no more than two drinks/day on average)
• Any excessive use of caffeine (more than six cups of coffee per day or equivalent)
• Any history of chronic alcohol or mood-altering drug abuse
• Any use of tobacco/nicotine products within 90 days of visit 1
• Any disease state or surgery known to affect the gastrointestinal absorption of drugs
• Treatment with an H1-receptor antagonist regularly within the past year before study entry
• Known hypersensitivity to the investigational product or to drugs with similar chemical properties, or to orange juice
• Need to visit a tanning salon during the study
• Need to use artificial tanning products during the study
• Pregnancy
• Breast-feeding
• Likelihood of requiring treatment during the study period with drugs not permitted by the clinical study protocol (see Section 6.2)
• Treatment with any investigational product in the last 30 days before study entry
• Clinically relevant cardiovascular, hepatic, neurologic, endocrine, or other major systemic disease making implementation of the protocol or interpretation of the study results difficult
• Mental condition rendering the subject unable to understand the nature, scope, and possible consequences of the study
• Unlikelihood of complying with protocol, e.g., uncooperative attitude, inability to return for follow-up visits, and unlikelihood of completing the study.
• Use of any of the following drugs within the time indicated prior to the first dosing visit (Time prior to Visit 2):
• Systemic or injected corticosteroids (including oral, parenteral, intravenous, rectal)(30 days).
• Nasal or inhaled or ocular corticosteroids (30 days).
• Nasal or inhaled ipratropium bromide (or atropine), inhaled nedocromil, or nasal, inhaled, or ophthalmic sodium cromolyn (14 days)
• Agents with antihistaminic/anticholinergic activity (e.g.antidepressants, antipsychotics)(14 days).
• Leukotriene pathway modifiers (Accolate®, Singulair®, Zyflo®) 10 days Ocular anti-allergy medications including lodoxamide (Alomide®), olopatadine (Patanol®), emedastine difumarate (Emadine®), levocabastine (Livostin®) (10 days).
• Non-steroidal anti-inflammatory ophthalmics including ketorolac (Acular®), flurbiprofen (Ocufen®), suprofen (Profenal®), diclofenac (Voltaren®) (10 days).
• Antihistamines including desloratadine (Clarinex®), loratadine (Claritin®)(10 days).
• Fexofenadine HCl (Allegra®), cetirizine (Zyrtec®), hydroxyzine, azelastine nasal spray (Astelin®), clemastine (7 days)
• Other short-acting antihistamines such as chlorpheniramine or drugs with antihistaminic activity (3 days).
• OTC oral antihistamines, decongestants (includes pseudoephedrine and other decongestants), or antihistamines/decongestant combinations including all cold, cough, and sleep aids (3 days).
• OTC ophthalmic decongestant, antihistamine, or decongestant/ antihistamine combinations (3 days).
• Other anticholinergic agents (3 days).
• Immunotherapy injection (1 day).
• Other drugs were to be permitted if they were not expected to interfere with the ability of the subject to participate in the study.
• Non-steroidal anti-inflammatory agents were not allowed for 2 days prior to each treatment visit day through 24 hours post-dose.
• Medications or agents not specified above that might confound the interpretation of the results were prohibited as follows:
• Caffeine within 6 hours prior to each visit (coffee, tea, cola, including Mountain Dew and Surge).
• Decaffeinated coffee, tea and colas within 6 hours of each visit
• Alcohol within 24 hours prior to each study visit.
• Chocolate within 6 hours prior to each visit.
• Antacids within + 2 hours of investigational product dosing.
• Any waiver of these inclusion and exclusion criteria required approval by the investigator and the sponsor on a case-by-case basis prior to enrolling the subject. Approval had to be documented by both the sponsor and the investigator.
• No subject was to be allowed to enroll in this study more than once.