This randomized clinical trial will evaluate the benefit of platelet-rich plasma (PRP) in the treatment of qualitative olfactory dysfunction (parosmia). PRP can be isolated from a patient's own blood and has been found in previous studies to have anti-inflammatory and pro-regenerative properties. It has been used across multiple specialties, such as Orthopedics, Facial Plastics, Dermatology, Neurology in injected form to treat a wide variety of tissues to encourage the body's inherent regenerative capacity. The investigators have completed a randomized controlled trial here, ending in 2022, evaluating it's use in post-SARS-CoV-2 olfactory loss which demonstrated safety and efficacy. Therefore, the investigators aim to assess the ability of PRP to improve olfactory function in patients with parosmia.

Inclusion Criteria:

• Patients >= 18 years of age
• Patients who have qualitative olfactory distortion
• Etiology of qualitative olfactory distortion is due to upper respiratory infection
• Quantitative score under the 10th percentile on the SSParoT (HedRang and HedDir)
• Quantitative score ≥ 8 on the QOD.
• At least 6 months of parosmia but less than 24 months
• Patients can have been previously treated with oral and topical steroids but this is not a requirement
• Patients will receive concurrent olfactory training - the practice of smelling strong odors (standard of care)
• Be able to read and understand English
• Be able and willing to provide Informed Consent

Exclusion Criteria:

• Patients < 18 years of age, pregnant females, patients who have structural abnormalities on nasal endoscopy or radiographic imaging that would prevent injection into the olfactory cleft
• Olfactory loss due to trauma, chronic sinusitis / inflammation / polyps, neoplasms, or neurodegenerative diseases or patients who have had olfactory loss > 24 months
• Patients with bleeding disorders or on blood thinners such as coumadin and plavix