# Pollen-Food Allergy Syndrome: Allergens, Clinical Insights, Diagnostic and Therapeutic Challenges
## 8 PFAS Management
### Pharmacological Treatment
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Drug Name** & **Generation** & **Formulation** & **Onset of Action** & **Duration of Action** & **Sedation** & **Common Uses in** \\  & & & & **Action** & **Potential** & **Allergies** \\ \hline
**Diphenhydramine** & First & Oral, Injectable & 15–30 min & 4–6 h & High & Acute allergic reactions, anaphylaxis adjunct \\ \hline
**Chlorpheniramine** & First & Oral & 30 min & 4–6 h & Moderate & Alleglergic rhinitis, mild allergic reactions \\ \hline
**Hydroxyzine** & First & Oral, Injectable & 15–30 min & 4–6 h & High & Anxiety-related \\  & & & & & & \\ \hline
**Cetriazine** & Second & Oral & 1 h & 24 h & Low & PEAS, allergic \\  & & & & & & \\ \hline
**Levocetriazine** & Second & Oral & 1 h & 24 h & Very Low & PEAS, chronic urticaria, allergic rhinitis \\ \hline
**Loratadine** & Second & Oral & 1–3 h & 24 h & Minimal & PEAS, allergic rhinitis \\ \hline
**Desloratadine** & Second & Oral & 1–3 h & 24 h & Minimal & PEAS, chronic \\  & & & & & & idiopathic urticaria \\ \hline
**Fexofenadine** & Second & Oral & 1 h & 24 h & None & PEAS, seasonal \\  & & & & & & allergic rhinitis \\ \hline
**Rupatadine** & Second & Oral & 1–2 h & 24 h & Very Low & PEAS, chronic urticaria, allergic rhinitis \\ \hline
**Bilastine** & Second & Oral & 1 h & 24 h & None & PEAS, allergic \\  & & & & & & rhinoconjunctivitis \\ \hline
**Ebastine** & Second & Oral & 1–3 h & 24 h & Low & Chronic urticaria, allergic rhinitis \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Overview of antihistamines acting on H1 receptors used in allergy management [249]. hyperglycemia, and adrenal suppression with prolonged use, must be carefully weighed against the benefits [252]. In clinical practice, systemic corticosteroids should only be used under close supervision, with particular attention to patients with comorbidities such as diabetes, osteoporosis, or hypertension, where corticosteroid use can exacerbate existing conditions. Furthermore, it is essential to counsel patients on the appropriate use of topical and systemic corticosteroids to minimize adverse effects and ensure effective symptom control [249]. Overall, while corticosteroids--both topical and systemic--play a limited role in PFAS management, they remain valuable adjuncts in specific clinical scenarios where inflammation leads to persistent discomfort or when severe allergic symptoms require more aggressive intervention. Although systemic reactions are rare in PFAS, certain patients are at an increased risk and may require additional precautions. Individuals sensitized to heat-stable allergens, such as LTPs, are particularly vulnerable, as these allergens can remain intact even after food is cooked. Therefore, LTPs can trigger more severe and systemic reactions, including gastrointestinal distress, generalized urticaria, or anaphylaxis [141]. For patients with a history of systemic reactions or more severe allergic symptoms, the provision of an epinephrine auto-injector for emergency use is strongly recommended. This precaution is essential not only for individuals with LTP sensitivity but also for those with overlapping food allergies (e.g., to nuts, seeds, or shellfish) or conditions that place them at a higher risk of anaphylaxis, such as mast cell disorders or poorly controlled asthma [98]. In these cases, the potential for a systemic reaction escalates, necessitating preparedness for immediate intervention [98,188]. Epinephrine auto-injectors should be prescribed alongside thorough patient education on their proper use [253]. Patients should be instructed to recognize the early signs of anaphylaxis, such as widespread hives, angioedema, difficulty breathing, dizziness, or gastrointestinal symptoms, and to use the auto-injector promptly if these symptoms occur. Clinicians should emphasize the importance of carrying the auto-injector at all times, particularly when consuming raw plant-based foods that are known to trigger PFAS or in situations where access to emergency medical care may be delayed [98].