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R RESPIRATORY SYSTEM

Inhaled antiinfectives are classified in ATC group J - Antiinfectives for systemic use.


R03 DRUGS FOR OBSTRUCTIVE AIRWAY DISEASES

R03A ADRENERGICS, INHALANTS

It is complicated to decide DDDs for the different dosage forms and even the different inhalation devices of the same dosage form. It has been shown that certain inhalation devices give a better deposition of the active ingredient in the lungs. This gives a better clinical effect, and therefore the active ingredients can be used in lower dosages. It has been decided not to take this aspect into consideration when assigning DDDs in this group, since the picture is very complex and satisfactory comparative documentation is not always available. Accordingly, only one DDD is assigned for one dosage form of a substance (e.g. powder inhalation).
For some substances, the labelling of the strength of identical inhalation products may differ between countries. In some countries, metered dose (measured as the amount of substance released from the inhaler with the mouthpiece removed) is used while in other countries delivered dose (measured as the amount of substance released from the inhaler with the mouthpiece in place) is used in the labelling. Delivered dose will usually be lower than metered dose. This is important to take into considerations when linking DDD information to the products in the different countries.
The DDDs for inhalation aerosol and inhalation powder of the same substance are in most cases given the same DDD value. The DDDs for inhalation solutions are, however, different from these and much higher, partly because less amount of the active ingredient will reach the target organ, and partly because this dosage form often is used in more severe asthma.

R03B OTHER DRUGS FOR OBSTRUCTIVE AIRWAY DISEASES, INHALANTS

This group comprises all drugs for obstructive airway diseases for inhalation excl. adrenergics (R03A).

See comment under R03A.

R03C ADRENERGICS FOR SYSTEMIC USE

This group comprises adrenergics for systemic use indicated for e.g. bronchial asthma. Sympathomimetics used in the treatment of hypotension, see C01CA. Fenoterol infusion only intended for repression of labour is classified in G02CA.
Combinations with xanthines are classified in R03DB. Combinations with other drugs for obstructive airway diseases belonging to R03D excl. xanthines are classified in R03CK.

R03D OTHER SYSTEMIC DRUGS FOR OBSTRUCTIVE AIRWAY DISEASES

Theophyllines are classified in this group. Other respiratory stimulants are classified in R07AB - Respiratory stimulants.
Corticosteroids for systemic use, see H02.
Sympathomimetics for systemic treatment of rhinitis, see R01BA.

This group comprises mainly the xanthines. The DDDs for these substances are based on treatment of obstructive lung diseases.

Last updated: 2024-01-26