Standard protocols are once daily, typically at bedtime on an empty stomach (at least two hours after the last meal), to align with the natural overnight growth hormone pulse window
CrossRef Pharmacokinetic Properties of Two Erlotinib 150 mg Formulations with a Genetic Effect Evaluation in Healthy Korean Subjects Hyun-Gyu Choi, Ji-Young Jeon, Yong-Jin Im, Yunjeong Kim, Eun-Kee Song, Young-Hwan Seo, Seok-Je Cho, Min-Gul Kim Clinical Drug Investigation.2015
10.20463/jenb.2016.0031 57
doi:10.1056/NEJMoa2411528 25
Equally do not discharge the symptomatic patient, you may have mis-timed the point of ingestion or the patient may have lied to you (about time or co-ingestants)
Ascorbate-Glutathione Pathway and Stress Tolerance in Plants