We present a rare case of severe neck pain in a 45-year-old man with severe hidradenitis suppurativa who was participating in a study involving adalimumab. The neck pain was associated with acute longus colli calcific tendinitis, which is a noninfectious inflammatory response in the longus colli tendons secondary to deposition of calcium hydroxyapatite crystal. The diagnosis was made by computed tomography, which showed calcifications and deposits, and magnetic resonance imaging, which showed a retropharyngeal effusion. Ears, Nose, and Throat Services performed a fiberoptic scope examination, which revealed a patent airway and no drainable abscess. Nonsteroidal anti-inflammatory drugs resulted in a dramatic improvement in the patient's clinical symptoms. In acute longus colli tendinitis, differentiating retropharyngeal aseptic effusion from infection is important. Of note, the confounding factor in this case was that the patient was blinded to whether he was receiving the placebo or adalimumab, so whether the patient was immunosuppressed and at risk for infection was unknown. Clinician familiarity and education concerning acute calcific longus colli tendinitis may lead to decreased costs stemming from incorrect diagnosis and unnecessary treatment.