20 The frequency of possible side effects listed below is defined using the following convention: very common (affects more than 1 user in 10), common (affects 1 to 10 users in 100), uncommon (affects 1 to 10 users in 1,000), rare (affects 1 to 10 users in 10,000), very rare (affects less than 1 user in 10,000), not known (frequency cannot be estimated from the available data).