Protocol·Immunity·Beginner·Reviewed June 9, 2026
Sinus & Respiratory Support Protocol.
A supportive, adjunctive stack aimed at thinning mucus, calming airway inflammation, and reinforcing normal immune defense at the sinus and respiratory mucosa. It is meant to complement, not replace, medical care for sinus, allergy, or respiratory conditions.
The sinus & respiratory support protocol in brief.
A quick summary. The full stack, with dose and timing for each supplement, is below.
The Sinus & Respiratory Support Protocol is a beginner stack of 6 supplements aimed at immunity: NAC, Quercetin, Vitamin C, Bromelain, Vitamin D3, and Probiotics. 4 are core and the rest are optional add-ons, at roughly $30-50/mo. Each supplement below lists its dose, timing, role, and the evidence behind it.
What is in the sinus & respiratory support protocol.
Dose, timing, role, and evidence tier for each supplement. Core items carry the protocol; optional ones are situational. Open any name for the full profile.
| Supplement | Dose | Timing | Role | Evidence |
|---|---|---|---|---|
| NAC | 600 mg, once or twice daily | With or between meals | Core | Moderate |
| Quercetin | 500 mg, once or twice daily | With meals | Core | Emerging |
| Vitamin C | 500 to 1000 mg daily | With meals, in split doses if above 500 mg | Core | Moderate |
| Bromelain | 500 mg (around 2000 GDU/g), once or twice daily | On an empty stomach, between meals | Optional | Emerging |
| Vitamin D3 | 1000 to 2000 IU daily | With a meal containing fat | Core | Moderate |
| Probiotics | 5 to 10 billion CFU daily | Morning, with or before breakfast | Optional | Moderate |
NAC is a precursor to glutathione with mucolytic activity that may help reduce mucus viscosity and support antioxidant defense in the airways. Evidence is strongest as supportive care in chronic bronchitis and COPD rather than as a cure.
Quercetin is a flavonoid that may stabilize mast cells and modestly dampen histamine release and inflammatory signaling, which could offer supportive relief for airway and allergic irritation. Human respiratory and allergy evidence remains preliminary.
Vitamin C is an antioxidant that supports normal immune cell function and mucosal integrity and may slightly shorten the duration of common colds. It supports respiratory defense rather than treating infection.
Bromelain is a pineapple-derived enzyme studied as a supportive aid for sinus congestion and inflammation, where it may help reduce nasal swelling and improve breathing comfort. Evidence is limited and adjunctive.
Vitamin D3 supports normal innate immune function at respiratory surfaces, and correcting low status may modestly reduce the risk of acute respiratory infections. Benefit is clearest in people who are deficient.
Certain probiotic strains may support balanced mucosal immunity and have been associated with a modest reduction in upper respiratory infection frequency and duration. Effects are strain dependent and supportive in nature.
How the pieces combine.
The mechanistic rationale for stacking these together rather than taking them in isolation.
- NAC thins mucus while Vitamin C supports mucosal antioxidant defense, a practical pairing for daytime clearance, and both are well tolerated together at these doses.
- Quercetin and Vitamin C are often combined because Vitamin C may help recycle quercetin's antioxidant activity, supporting the airway anti-inflammatory angle. Take both with meals to limit stomach upset.
- Take Bromelain on an empty stomach, separated by at least 1 to 2 hours from food-based supplements like Vitamin D3, so its enzyme activity targets inflammation rather than digesting your meal.
- Separate Probiotics from NAC by a couple of hours when possible. NAC's antioxidant load is unlikely to harm cultures, but spacing helps each act on its own target.
- Safety: people on blood thinners or with a pineapple allergy should ask a clinician before adding Bromelain or high-dose Quercetin, and anyone who is pregnant, immunocompromised, or taking nitroglycerin should check with a clinician before starting NAC or Probiotics.
- This stack is supportive and adjunctive only: it does not treat, cure, or replace prescribed care for sinusitis, asthma, or other respiratory conditions, and persistent, severe, or worsening symptoms warrant prompt medical evaluation.
Cost and commitment.
A rough monthly cost and how involved the protocol is to run.
The evidence behind it.
Overview citations for this protocol. Each supplement's own profile carries its full source list.
- Martineau AR et al. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. BMJ. 2017;356:i6583. PubMed
- Hemilä H et al. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2013;2013(1):CD000980. PubMed
- Cazzola M et al. Influence of N-acetylcysteine on chronic bronchitis or COPD exacerbations: a meta-analysis. Eur Respir Rev. 2015;24(137):451-61. PubMed
Common questions.
Quick answers drawn from the stack above.
What is in the Sinus & Respiratory Support Protocol?
The Sinus & Respiratory Support Protocol combines 6 supplements for immunity: NAC, Quercetin, Vitamin C, Bromelain, Vitamin D3, and Probiotics. 4 are core; the rest are optional.
How much does the Sinus & Respiratory Support Protocol cost?
NutriStack estimates the Sinus & Respiratory Support Protocol at about $30-50/mo, depending on the forms and brands you choose and whether you run the optional add-ons.
Is the Sinus & Respiratory Support Protocol backed by evidence?
Each supplement in the protocol carries its own evidence tier (0 rated strong here) and links to PubMed-cited sources. NutriStack does not rank or score brands and takes no manufacturer payments; this is an informational reference, not medical advice.
Build it in the app
Run the sinus & respiratory support protocol in NutriStack.
Add the stack to NutriStack to track timing, screen it for interactions, and see a Stack Score that updates as you tune it.