For Inhaler shortages use the below conversion:

Atrovent HFA 4 puffs = Atrovent nebs 0.25mg

Atrovent HFA 8 puffs = Atrovent nebs 0.5mg

For Non-formulary to Formulary interchange:

Spiriva 1.25mcg 1-2 inhalation daily ----- Ipratropium 0.5mg nebulized daily

Spiriva 2.5mcg 1-2 inhalation daily ------  Ipratropium 0.5mg nebulized daily 

Standardized neb dosing:

< 30kg = 0.25mg nebs

> 30kg = 0.5mg nebs

• Micromedex Drug Information
• FDA Daily Med Package Insert
• Recent Citations via Medline (PubMed)
• WebMD Pill Identifier