• Change from baseline in the subject's mean reflective Total Nasal Symptom (TNS) Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean instantaneous TNS Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean reflective Total SAR Symptom (TSS) Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean instantaneous TSS Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean reflective score for each of the seven remaining individual SAR symptoms, excluding nasal congestion/stuffiness [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean instantaneous score for each of the eight individual SAR symptoms [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Onset of action for diphenhydramine treatment for nasal congestion/stuffiness was determined by comparing the change from baseline in the subject's instantaneous nasal congestion/stuffiness scores for diphenhydramine versus placebo [ Time Frame: taken at 15, 30, 60 and 90 minutes after the initial dose. Baseline was the score taken just prior to the initial dose. ] [ Designated as safety issue: No ]
• Onset of action for diphenhydramine treatment for allergic rhinitis symptoms was determined by comparing the change from baseline in the subject's instantaneous TNS scores for diphenhydramine versus placebo [ Time Frame: taken at 15, 30, 60 and 90 minutes after the initial dose. Baseline was the score taken just prior to the initial dose ] [ Designated as safety issue: No ]
• Duration of action for diphenhydramine for treatment of nasal congestion/stuffiness was evaluated by comparing the change from baseline in the subject's mean instantaneous nasal congestion/stuffiness scores for diphenhydramine versus placebo [ Time Frame: taken at the six-hour trough (just prior to the 8:00 pm dose) and the 12-hour trough (just prior to the 8:00 am dose) ] [ Designated as safety issue: No ]
• Duration of action for diphenhydramine for treatment of allergic rhinitis symptoms was evaluated by comparing the change from baseline in the subject's mean instantaneous TNS scores for diphenhydramine versus placebo [ Time Frame: taken at the six-hour trough (just prior to the 8:00 pm dose) and the 12-hour trough (just prior to the 8:00 am dose) ] [ Designated as safety issue: No ]
• Time to maximal effect was assessed by a by-day analysis of the primary efficacy endpoint and select secondary endpoints [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Subject's global evaluation of response to treatment [ Time Frame: at Visits 3 and 4, analyzed separately at each visit ] [ Designated as safety issue: No ]
• Change from baseline in the Investigator's TNS score [ Time Frame: at Visits 3 and 4, analyzed separately for each visit. Baseline was the score at Visit 1 ] [ Designated as safety issue: No ]
• Change from baseline in the Investigator's TSS score [ Time Frame: at Visits 3 and 4, analyzed separately for each visit. Baseline was the score at Visit 1 ] [ Designated as safety issue: No ]
• Change from baseline for each of the eight individual Investigator's SAR symptoms [ Time Frame: at Visits 3 and 4, analyzed separately for each visit. Baseline was the score at Visit 1 ] [ Designated as safety issue: No ]
• Investigator's global evaluation of the subject's response to treatment [ Time Frame: at Visits 3 and 4, analyzed separately for each visit ] [ Designated as safety issue: No ]
• Number and percentage of subjects experiencing adverse events [ Time Frame: Duration of study ] [ Designated as safety issue: No ]
• Change from baseline and potentially clinically important vital signs (systolic and diastolic blood pressure, pulse, and respiratory rate) [ Time Frame: Duration of study ] [ Designated as safety issue: No ]
• Occurrence of somnolence [ Time Frame: Overall and weekly ] [ Designated as safety issue: No ]

• Change from baseline in the subject's mean reflective Total Nasal Symptom (TNS) Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean instantaneous TNS Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean reflective Total SAR Symptom (TSS) Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean instantaneous TSS Score [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean reflective score for each of the seven remaining individual SAR symptoms, excluding nasal congestion/stuffiness [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Change from baseline in the subject's mean instantaneous score for each of the eight individual SAR symptoms [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Onset of action for diphenhydramine treatment for nasal congestion/stuffiness was determined by comparing the change from baseline in the subject's instantaneous nasal congestion/stuffiness scores for diphenhydramine versus placebo [ Time Frame: taken at 15, 30, 60 and 90 minutes after the initial dose. Baseline was the score taken just prior to the initial dose. ] [ Designated as safety issue: No ]
• Onset of action for diphenhydramine treatment for allergic rhinitis symptoms was determined by comparing the change from baseline in the subject's instantaneous TNS scores for diphenhydramine versus placebo [ Time Frame: taken at 15, 30, 60 and 90 minutes after the initial dose. Baseline was the score taken just prior to the initial dose ] [ Designated as safety issue: No ]
• Duration of action for diphenhydramine for treatment of nasal congestion/stuffiness was evaluated by comparing the change from baseline in the subject's mean instantaneous nasal congestion/stuffiness scores for diphenhydramine versus placebo [ Time Frame: taken at the six-hour trough (just prior to the 8:00 pm dose) and the 12-hour trough (just prior to the 8:00 am dose) ] [ Designated as safety issue: No ]
• Duration of action for diphenhydramine for treatment of allergic rhinitis symptoms was evaluated by comparing the change from baseline in the subject's mean instantaneous TNS scores for diphenhydramine versus placebo [ Time Frame: taken at the six-hour trough (just prior to the 8:00 pm dose) and the 12-hour trough (just prior to the 8:00 am dose) ] [ Designated as safety issue: No ]
• Time to maximal effect was assessed by a by-day analysis of the primary efficacy endpoint and select secondary endpoints [ Time Frame: 14 Days ] [ Designated as safety issue: No ]
• Subject's global evaluation of response to treatment [ Time Frame: at Visits 3 and 4, analyzed separately at each visit ] [ Designated as safety issue: No ]
• Change from baseline in the Investigator's TNS score [ Time Frame: at Visits 3 and 4, analyzed separately for each visit. Baseline was the score at Visit 1 ] [ Designated as safety issue: No ]
• Change from baseline in the Investigator's TSS score [ Time Frame: at Visits 3 and 4, analyzed separately for each visit. Baseline was the score at Visit 1 ] [ Designated as safety issue: No ]
• Change from baseline for each of the eight individual Investigator's SAR symptoms [ Time Frame: at Visits 3 and 4, analyzed separately for each visit. Baseline was the score at Visit 1 ] [ Designated as safety issue: No ]
• Investigator's global evaluation of the subject's response to treatment [ Time Frame: at Visits 3 and 4, analyzed separately for each visit ] [ Designated as safety issue: No ]
• Number and percentage of subjects experiencing adverse events [ Time Frame: Duration of study ] [ Designated as safety issue: Yes ]
• Change from baseline and potentially clinically important vital signs (systolic and diastolic blood pressure, pulse, and respiratory rate) [ Time Frame: Duration of study ] [ Designated as safety issue: Yes ]
• Occurrence of somnolence [ Time Frame: Overall and weekly ] [ Designated as safety issue: Yes ]

The study was to determine if the drug worked to relieve nasal congestion experienced by people with seasonal allergies.

Subjects who met the inclusion/exclusion criteria were enrolled into the placebo run-in phase of the study on Day -7 (prerandomization, Visit 1). Baseline symptom scores were established during this run-in phase.

Subjects with moderate nasal congestion who took at least 80% of their study medication during the run-in phase were eligible for enrollment in the two-week double-blind phase of the study and were randomized on Day 1 (randomization, Visit 2). They were treated for two weeks with their assigned medication. The severity of signs/symptoms were evaluated by the subjects every morning and night and by the investigator at each visit on Day 7 and Day 14.

In addition, the subject and investigator provided a global evaluation of response to treatment on Day 7 and Day 14. Safety was evaluated by adverse events reported during the study, vital signs, and the incidence of somnolence.

• Drug: Diphenhydramine 50 mg
• Drug: Diphenhydramine 25 mg
• Drug: Pseudoephedrine 120 mg

• Experimental: Diphenhydramine 50 mg
• Experimental: Diphenhydramine 25 mg
• Active Comparator: Pseudoephedrine 120 mg

Inclusion Criteria:

• otherwise healthy males and females
• 12 to 65 years of age
• hypersensitivity to specific pollens for a minimum of 2 years prior to study start
• appropriate SAR sign/symptoms scores

Exclusion Criteria:

• pregnancy, lactation and contraception issues
• contraindicated medications or therapies
• evidence of clinical, dietary, lifestyle or psychiatric issues, which in the opinion of the investigator, could increase the risk to the subject or research staff, or interfere with the interpretation of study results