Study objective is to verify the superiority of CTZ DS to the placebo groups in the change of total nasal symptom score (TNSS) over the total treatment period from the score of the baseline assessment period.

Inclusion criteria:

- [Before the start of observation period]

1. Children with a history of hypersensitivity to an ingredient of cetirizine hydrochloride preparation, or hydroxyzine, cyclizine, meclozine, buclizine.

   • Children with a history of drug hypersensitivity.

   • Pregnant, lactating or possibly pregnant female children.

   • Children with complications that may be clinically significant (e.g., hepatic disorder, renal disorder, heart disease or others) because of which they are judged as inappropriate for this trial.

   • Children who are sensitive to pollen as a duplicate allergen and whose treatment periods are thought in the pollen dispersion periods.

   • Children with vasomotor rhinitis and eosinophilic rhinitis.

   • Children complicated with a nasal disorder (e.g., acute or chronic rhinitis, hypertrophic rhinitis, acute or chronic sinusitis, deviation of nasal septum, nasal polyp, etc.) with a degree that may influence on the evaluation of the study drugs.

   • Children complicated with asthma that requires the treatment with adrenocortical hormone (including the preparations compounded with adrenocortical hormone).

   • Children administered the following drugs within one week (6days) or 4 weeks (27days) before the start of the observation period [within one week] • Anti-histamine drugs (oral, injection, and nasal drop) • Chemical mediator release inhibitors (mast cell stabilizer) • Th2 cytokine inhibitors (suplatast tosilate) • Leukotriene receptor antagonists • Thromboxane A2 receptor antagonists

     • Thromboxane synthetase inhibitors

     • Biological preparations and vaccines indicated against allergic rhinitis

     • Vasoconstrictor(oral and nasal drop)

     • Anticholinergic drugs (inhalant only)

     • General cold remedies (including OTC)

     • Herb medicines that have antiallergic action (SHOSEIRYUTO, SHOSAIKOTO, SAIBOKUTO, etc.)

     • OTC anti-rhinitis drugs (oral, inhalant, nasal drop) [within 4 weeks]

     • Adrenocortical hormones (oral [including combination drugs], injection, inhalant, nasal drop, suppository)

     • Histamine added γ-globulin preparations

   • Children who have started specific desensitization treatment or nonspecific modulation treatment but who have not reached the maintenance level of treatment.

   • Children who have received surgical treatment for reduction and modulation of nasal mucosa, redintegration therapy of nasal cavity to improve the degree of nasal airway, or surgical operation to improve rhinorrhea.

   • Children who have previously taken the investigational products of this trial.

   • Children who have participated in other clinical trial within 6 months of the date of informed consent for this clinical study or children who are participating in another trial as of the date of informed consent for this trial.

   • Children judged by the investigator or sub-investigator as inappropriate to participate in the trial.

[Before the start of treatment period] - Children whose severity score calculated by the following formula on the basis of nasal symptom score (sneezing, rhinorrhea, nasal pruritus and nasal congestion) in the baseline assessment period (3 days from D5 to D7) is 10 or higher Severity of TNSS = [TDNSS(D-3)+TDNSS(D-2)+TDNSS(D-1)]/3

• Children who have used prohibited concomitant drugs during the observation period.
• Children who have complicated acute upper airway inflammation during the observation period.
• Children who are applicable to the exclusion criteria as to the status [before the start of observation period] during the observation period." gher

Exclusion criteria:

"[Before the start of observation period]

1. Children with a history of hypersensitivity to an ingredient of cetirizine hydrochloride preparation, or hydroxyzine, cyclizine, meclozine, buclizine.

2. Children with a history of drug hypersensitivity.

3. Pregnant, lactating or possibly pregnant female children.

4. Children with complications that may be clinically significant (e.g., hepatic disorder, renal disorder, heart disease or others) because of which they are judged as inappropriate for this trial.

5. Children who are sensitive to pollen as a duplicate allergen and whose treatment periods are thought in the pollen dispersion periods.

6. Children with vasomotor rhinitis and eosinophilic rhinitis.

7. Children complicated with a nasal disorder (e.g., acute or chronic rhinitis, hypertrophic rhinitis, acute or chronic sinusitis, deviation of nasal septum, nasal polyp, etc.) with a degree that may influence on the evaluation of the study drugs.

8. Children complicated with asthma that requires the treatment with adrenocortical hormone (including the preparations compounded with adrenocortical hormone).

9. Children administered the following drugs within one week (6days) or 4 weeks (27days) before the start of the observation period [within one week]

   • Anti-histamine drugs (oral, injection, and nasal drop)

   • Chemical mediator release inhibitors (mast cell stabilizer)

   • Th2 cytokine inhibitors (suplatast tosilate)

   • Leukotriene receptor antagonists

   • Thromboxane A2 receptor antagonists

   • Thromboxane synthetase inhibitors

   • Biological preparations and vaccines indicated against allergic rhinitis

   • Vasoconstrictor(oral and nasal drop)

   • Anticholinergic drugs (inhalant only)

   • General cold remedies (including OTC)

   • Herb medicines that have antiallergic action (SHOSEIRYUTO, SHOSAIKOTO, SAIBOKUTO, etc.)

   • OTC anti-rhinitis drugs (oral, inhalant, nasal drop) [within 4 weeks]
   • Adrenocortical hormones (oral [including combination drugs], injection, inhalant, nasal drop, suppository)
   • Histamine added γ-globulin preparations

10. Children who have started specific desensitization treatment or nonspecific modulation treatment but who have not reached the maintenance level of treatment.

11. Children who have received surgical treatment for reduction and modulation of nasal mucosa, redintegration therapy of nasal cavity to improve the degree of nasal airway, or surgical operation to improve rhinorrhea.

12. Children who have previously taken the investigational products of this trial.

13. Children who have participated in other clinical trial within 6 months of the date of informed consent for this clinical study or children who are participating in another trial as of the date of informed consent for this trial.

14. Children judged by the investigator or sub-investigator as inappropriate to participate in the trial.

[Before the start of treatment period]

1） Children whose severity score calculated by the following formula on the basis of nasal symptom score (sneezing, rhinorrhea, nasal pruritus and nasal congestion) in the baseline assessment period (3 days from D5 to D7) is 10 or higher Severity of TNSS = [TDNSS(D-3)+TDNSS(D-2)+TDNSS(D-1)]/3 2) Children who have used prohibited concomitant drugs during the observation period.

3) Children who have complicated acute upper airway inflammation during the observation period.

4) Children who are applicable to the exclusion criteria as to the status [before the start of observation period] during the observation period."