You can schedule your child for our next available appointment by calling us at the number below. Prima Pediatrics. 18520 Via Princessa. Canyon Country, CA 91387. Phone number. (661) 424-9000. Fax number. (661) 424-0808. If you are a current patient you can reach our after-hours on-call provider by dialing the above number and following the ...ABOUT US‧PATIENT INFORMATION‧SERVICES‧CONTACT US‧Our Office‧Dr. Feldman.