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N NERVOUS SYSTEM
N02 ANALGESICS

This group comprises general analgesics and antipyretics.
All salicylic acid derivatives except combinations with corticosteroids (M01B) or opioids (N02AJ) are classified in N02BA - Salicylic acid and derivatives, as it is difficult to differentiate between the use of salicylates in rheumatic conditions and other therapeutic uses of salicylates.
All plain ibuprofen preparations are classified in M01A, even if they are only intended for use as pain relief.
There are a number of combined preparations, which contain analgesics and psycholeptics. These are classified in N02, as pain relief must be regarded as the main indication. Analgesics used for specific indications are classified in the respective ATC groups. E.g.:
A03D/
A03EA- Antispasmodic/psycholeptics/analgesic combinations
M01 - Antiinflammatory and antirheumatic products
M02A - Topical products for joint and muscular pain
M03 - Muscle relaxants
See comments to these groups.
Lidocaine indicated for postherpetic pain is classified in N01BB.


N02A OPIOIDS

This group comprises strong analgesics of the opiate type and analgesics with similar structure or action.
Sufentanil, which is also used as an epidural analgesic or in postoperative pain, is classified in N01AH.
Fentanyl in combination with bupivacaine used in e.g. postoperative pain is classified in N01AH51 - fentanyl, combinations.
Combinations with antispasmodics are classified in N02AG.

The DDDs in this group are based on the treatment of pain.
The DDD for oral morphine is higher than the parenteral DDD because of lower bioavailability.


N02AA Natural opium alkaloids

This group includes natural and semi-synthetic opiates.
All plain morphine preparations are classified in this group.
Opium, see also A07DA - Antipropulsives.
Plain codeine preparations are classified in R05D - Cough suppressants, excl. combinations with expectorants, while dihydrocodeine is classified in N02AA. Codeine or dihydrocodeine in combination with other analgesics or NSAIDs are classified in N02AJ - Opioids in combination with non-opioid analgesics.
Other combinations with e.g. caffeine, antihistamines and anticholinergic agents are classified in N02AA. Combinations of codeine with psycholeptics are classified in N02AA79.

The DDDs are based on approved dose recommendations.
When establishing DDDs for combination products in the 50-series, all analgesic components are taken into consideration.
The DDD, expressed in UD, should normally not exceed the approved dose recommendations for any of the components.
See list of DDDs for combination products, www.whocc.no.

N02AB Phenylpiperidine derivatives

Fentanyl patches are classified in this group whereas parenteral formulations are classified in N01AH.

The transdermal DDD for fentanyl is based on the amount delivered per 24 hours.

N02AC Diphenylpropylamine derivatives

Methadone, levomethadone and levacetylmethadol are classified in N07BC - Drugs used in opioid dependence.
Dextropropoxyphene in combination with a muscle relaxant is classified in M03B.

Different DDDs are assigned for different dextropropoxyphene salts based on their different solubility.

N02AD Benzomorphan derivatives
N02AE Oripavine derivatives

High strength formulations (above 0.4 mg) of buprenorphine used in opioid dependence are classified in N07BC.

N02AF Morphinan derivatives
N02AG Opioids in combination with antispasmodics

Preparations are classified at 5th levels according to the analgesic. At each level different antispasmodics may occur.

The DDDs in this group are as far as possible equipotent to the DDD for parenteral morphine.

N02AJ Opioids in combination with non-opioid analgesics

Includes combinations with opioids and other non-opioid analgesics (e.g. paracetamol, acetylsalicylic acid or NSAIDs). At each 5th level other active ingredients such as e.g. caffeine, vitamins and antihistamines are allowed.
Various combinations of codeine with other analgesics are included in N02AJ09 - codeine and other non-opioid analgesics. For example combinations containing three analgesic components (codeine, paracetamol and ibuprofen) are classified in N02AJ09.
Various combinations of tramadol with other analgesics are included in N02AJ15 - tramadol and other non-opioid analgesics. For example combinations containing tramadol and ibuprofen (or ketorolac or diclofenac) are classified in N02AJ15.
Combinations of benzhydrocodone and paracetamol are classified in N02AJ22.
Combinations of codeine, non-opioid analgesics and psycholeptics are classified in N02AA79 - codeine, combinations with psycholeptics. Other analgesics may be included in the 70-series codes.
All plain and combination products containing dextropropoxyphen are classified in N02AC.

The DDDs are based on approved dose recommendations.
When establishing DDDs for combination products all analgesic components are taken into consideration.
The DDD, expressed in UD, should normally not exceed the approved dose recommendations for any of the components.
See list of DDDs for combination products, www.whocc.no.

N02AX Other opioids

The group comprises opioids, which cannot be classified in the preceding groups.

Last updated: 2024-01-26