- Packed Cell Volume
- PAPP-A
- Parietal Cell Antibody
- Phenobarbital (Cardinal)
- Phenytoin (Eptoin)
- Phosphorus
- Platelet Count
- Porphobilinogen (PBG)
- Porphobilinogen (qualitative)
- Potassium
- Pregnancy Test
- Procalcitonin
- Progesterone
- Prolactin
- Protein – 24 hrs Urine
- Protein – Fluids
- Protein – Random (Spot)
- Protein C
- Protein Electrophoresis
- Protein Electrophoresis (Oligoclonal Bands)
- Protein S
- Protein Total
- Protein Total with Albumin
- Protein/Creatinine Ratio
- Prothrombin Time (PT)
- PSA, Total – Prostate Specific Antigen