Patchy basal opacities on chest X-Ray occurring in the first 24 hours are reasonably common in patients with poisoning. The drugs that lead to this are usually sedating (e.g. benzodiazepines), emetogenic (e.g. chloroquine) or both (e.g. alcohol). In most cases the condition causes more X-ray findings than clinical problems. If the patient does not have a fever or any respiratory compromise then expectant treatment is probably all that is required. The initial 'pneumonia' is usually a mild chemical pneumonitis and atelectasis rather than a bacterial infection. Chest physiotherapy (deep breathing and coughing) and supplemental oxygen, if necessary, are the most important aspects of treatment. Antibiotics are usually not required.
A severe aspiration pneumonia or chemical pneumonitis is unusual except with aspiration of fuels (e.g. petrol & kerosene) or hydrocarbons of other types (e.g. diluents or propellants for pesticides). The major problem with the lungs of these patients is widespread destruction of surfactant and inflammation from a chemical burn by the hydrocarbons. Treatment is essentially the same as for Adult Respiratory Distress Syndrome and is primarily through respiratory support (ventilation, PEEP and oxygen).
Prophylactic antibiotics or steroids are not indicated for gastric aspiration (Wolfe et al 1977).
Wolfe JE, Bone RC, Ruth WE. Effects of corticosteroids in the treatment of patients with gastric aspiration. Am J Med 1977; 63(5):719-722.