Cognomen Promkam (Promkam 
) , globally, is a rare surname. The cognomen Promkam is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname.
| VARIANT | COUNTRY |
|---|---|
| Promkam | Thailand |
| ratthaprom promkam Dr. rer. nat. Bayerische Julius-Maximilians-Universität Würzburg 2019 |
|