Coldamaris lozenges are a medical device containing 10 mg carrageenan/lozenge. The goal of the study is to determine whether the iota-carrageenan content in the saliva of subjects who sucked Coldamaris® lozenges is sufficient to inhibit the replication of 4 of the most common respiratory viruses causing common cold. At least 29 subjects will be screened, in order to get 24 subjects included.

Coldamaris lozenges are a medical device containing 10 mg carrageenan/lozenge. The goal of the study is to determine whether the iota-carrageenan content in the saliva of subjects who sucked Coldamaris® lozenges is sufficient to inhibit the replication of 4 of the most common respiratory viruses causing common cold. At least 29 subjects will be screened, in order to get 24 subjects included.

The primary objective is whether the mean iota-carrageenan concentration in saliva during sucking an iota-carrageenan containing lozenge reaches published IC90 values for HRV1a and HRV8.

The secondary objectives are whether the mean iota-carrageenan concentration in saliva (µg/ml; base line corrected) during sucking an iota-carrageenan containing lozenge reaches the respective IC90/MIC values (paired t-tests) of the clinical saliva samples for HRV1a, HRV8, hCoV OC43, influenza virus H1N1n and Coxsackie virus A10.

Inclusion Criteria:

• personally signed and dated informed consent
• healthy respiratory tract, no acute infection
• age > 18 years

Exclusion Criteria:

• subjects with signs of an acute respiratory infection
• subjects with a known hypersensitivity to one of the ingredients
• presence of pregnancy confirmed