- In dogs and cats
- Free radical release causes damage to air-blood barrier
- Depending on the dose, the lesions range from acute lesions (oedema, haemorrhage, hyaline membranes) -> chronic (fibroplasia of alveolar septae, replacement of alveolar cells with type II cells)
- Additional extrapulmonary lesions to note following paraquat intoxication are necrosis of the adrenal zona glomerulosa and renal tubular epithelium
- Causes Interstitial Pneumonia