Meanings of per os in inglés

Post-operative course was uneventful, with return to a normal diet per os on the first post-operative day.

After surgery all patients were maintained with nil per os until a barium swallow showed no leakage.

Anticancer effect of BC1 administered per os was evaluated by the indexes of tumor growth inhibition and average life span of experimental animals.

The same protocol was repeated after a two-month course of treatment with MT, 2 mg per os daily at 1800.

As two control groups, we selected 337 Caucasian diabetic patients receiving antidiabetic drugs per os and 1,988 healthy Caucasian volunteers who had been genotyped earlier.