N 

Namibia

Nauru

Nepal

Netherlands

New Zealand

Buprenorphine-PO(SL with naloxone),IV,TD
Codeine-PO,IV
Fentanyl-IV,TD
Methadone-PO,IV
Morphine-PO,IV;IR,SR
Oxycodone-IR,SR
Tramadol-PO,IV;IR,SR

Contributor: A.D. (Sandy) Macleod

Nicaragua

Niger

Nigeria

Dihydrocodeine - PO,IV
Fentanyl - IV
Morphine - PO,IV
Pentazocine - PO,IV
Pethidine - IV

Contributor: Olaitan Soyannwo

Norway