Dry air-induced nasal mucosal irritation: The patient's daily nosebleeds, combined with a history of allergies, suggest that dry air or environmental irritants may be causing nasal mucosal irritation, leading to frequent nosebleeds. The presence of iron deficiency anemia also supports this diagnosis, as frequent nosebleeds can contribute to anemia.

Nasal septal deviation or other anatomical abnormalities: The patient's history of allergies and nosebleeds suggests that an underlying anatomical issue, such as a deviated septum, may be contributing to the nosebleeds.
Hypertension: Although not directly mentioned, the patient's use of metformin ER 2000 mg daily may indicate a diagnosis of polycystic ovary syndrome (PCOS) or insulin resistance, which can increase the risk of hypertension. Uncontrolled hypertension can cause nosebleeds.
Platelet dysfunction or thrombocytopenia: The patient's iron deficiency anemia and use of medications such as quetiapine and sertraline may increase the risk of platelet dysfunction or thrombocytopenia, which can contribute to nosebleeds.

Nasopharyngeal cancer: Although rare, nasopharyngeal cancer can cause recurrent nosebleeds, and it is essential to rule out this diagnosis, especially in a patient with a history of allergies and nosebleeds.
Granulomatosis with polyangiitis (GPA): GPA is a rare autoimmune disorder that can cause recurrent nosebleeds, sinusitis, and other respiratory symptoms. It is crucial to consider this diagnosis, especially if the patient has other systemic symptoms.
Hereditary hemorrhagic telangiectasia (HHT): HHT is a rare genetic disorder that can cause recurrent nosebleeds, telangiectasias, and other vascular malformations. Although unlikely, it is essential to consider this diagnosis, especially if the patient has a family history of similar symptoms.

Vitamin K deficiency: Although rare, vitamin K deficiency can cause coagulopathy and increase the risk of nosebleeds. This diagnosis is unlikely but should be considered if the patient has a restricted diet or malabsorption.
Scurvy: Scurvy is a rare condition caused by vitamin C deficiency, which can cause connective tissue weakness, leading to nosebleeds. This diagnosis is unlikely but should be considered if the patient has a restricted diet or malabsorption.
Leukemia or lymphoma: Although rare, leukemia or lymphoma can cause thrombocytopenia, coagulopathy, or nasal mucosal infiltration, leading to recurrent nosebleeds. These diagnoses are unlikely but should be considered if the patient has other systemic symptoms or abnormal laboratory results.