Background: Despite evidence that opioids might relieve chronic breathlessness, physicians may still be reluctant to prescribe them due to safety concerns. By contrast, benzodiazepine (BDZ) prescribing often seeks to reduce chronic breathlessness despite no evidence of net benefit. Prescribing patterns and indications for these medications in severe interstitial lung disease (ILD) are unknown. Here, our objective was to evaluate the indications, medications and temporal patterns of BDZ and opioid prescriptions in people with oxygen-dependent ILD. Methods: This was an observational, population-based, longitudinal study of adults starting long-term oxygen therapy (LTOT) for ILD between 2005 and 2014 in the Swedish National Registry for Respiratory Failure (Swedevox). People dispensed BDZs (n=2000) and opioids (n=2000) from 6 months before start of LTOT throughout follow-up (first of death or study end) were analysed. Results: Of 1635 included patients, 651 (39.8%) received BDZs and 710 (43.4%) received opioids during the study period; 373 (22.8%) patients received both. The most frequently prescribed BDZs and opioids were oxazepam (85.6%) and oxycodone (28.7%), respectively. Indications for breathlessness were uncommon for BDZs (1.4%) and opioids (6.4%). During the last year of life, opioid indications for breathlessness increased from 2.5% (12���10 months before death) to 10.2% in the last 3 months of life (p=0.048). Conclusions: In oxygen-dependent ILD, opioids are rarely prescribed for breathlessness even in the last months of life, when chronic breathlessness often increases in prevalence and intensity.