# Pollen-Food Allergy Syndrome: Allergens, Clinical Insights, Diagnostic and Therapeutic Challenges
## 8 PFAS Management
### Pharmacological Treatment  
Pharmacological treatment for PFAS primarily aims to manage symptoms and improve quality of life, particularly for patients experiencing frequent or severe reactions. However, even though PFAS symptoms are generally mild and localized, pharmacological interventions can be helpful in mitigating discomfort, especially when food avoidance alone is insufficient or impractical. Oral antihistamines are the mainstay of pharmacological management in PFAS, similar to their role in other allergic conditions. Antihistamines primarily act as H1 receptor inverse agonists to block the effects of histamine at H1 receptors. Unlike traditional antagonists, which simply block a receptor from being activated by an agonist, an inverse agonist actively reduces the receptor's intrinsic activity even in the absence of a natural ligand (like histamine) [248]. By blocking H1 histamine receptors, these medications effectively reduce symptoms such as itching, tingling, or mild swelling associated with OAS. They are fast-acting, widely available, and generally well-tolerated. Non-sedating second-generation antihistamines, such as loratadine, cetriazine, or kefofenadine, are preferred due to their favorable side effect profiles [31]. These medications are typically used on an as-needed basis before consuming known trigger foods or during peak pollen seasons when cross-reactivity tends to be heightened. Antihistamines are broadly classified into first-generation (sedating) and second-generation (non-sedating) agents, with the latter being preferred for PFAS due to their favorable safety and side-effect profiles. Table 5 provides an overview of commonly used H1 antihistamines, including their generation, receptor specificity, pharmacokinetics, sedation potential, and clinical applications in allergic diseases including PFAS. For patients with persistent or more severe symptoms, short courses of topical corticosteroids may be considered to reduce inflammation and provide symptomatic relief, particularly when oral antihistamines alone are insufficient. These include corticosteroid mouth rinses (e.g., dexamethasone or betamethasone solutions) or corticosteroid sprays (e.g., flutticasone or budesonide), which can target inflammation directly in the oral cavity. These formulations are generally well-tolerated, with minimal systemic absorption when used as directed, making them a suitable option for managing localized symptoms such as oral itching, burning, or swelling [250]. Systemic corticosteroids, on the other hand, are rarely required in the management of PFAS because the symptoms are typically mild, transient, and limited to the oral cavity. The use of systemic corticosteroids, such as oral prednisolone, is generally reserved for more severe presentations, such as cases where reactions extend beyond the oral cavity, such as gastrointestinal symptoms (e.g., abdominal pain, nausea), significant angioedema, or systemic discomfort [251]. In these rare situations, a short course of systemic corticosteroids may help to rapidly reduce inflammation and alleviate symptoms. However, the risks of systemic side effects, including weight gain,