Montelukast Shortage: What Providers and Prescribers Need to Know in 2026

As a prescriber, you're increasingly fielding calls from patients who cannot fill their montelukast prescriptions. While montelukast is not in a formal FDA-declared national shortage as of 2026, localized supply gaps — particularly for pediatric formulations — continue to create clinical management challenges. This guide provides an up-to-date clinical overview for providers navigating these issues.

Current Availability Status

Montelukast (generic Singulair) has been off-patent since August 2012 and is produced by numerous generic manufacturers. The FDA drug shortage database does not currently list montelukast as a nationwide shortage drug. The national supply of the 10 mg adult tablet is generally stable.

However, prescribers and pharmacists across the country are reporting localized difficulties, particularly with:

4 mg oral granule packets (for patients 6–23 months) — fewest manufacturers; most prone to localized gaps

4 mg and 5 mg chewable tablets (for children 2–14) — fewer manufacturers than the adult tablet; seasonal shortages possible

Brand-name Singulair — rarely stocked by most retail pharmacies; special order typically required

Clinical Context: Prescribing Landscape After the 2020 Boxed Warning

In March 2020, the FDA required a black box warning for montelukast due to serious neuropsychiatric events, including suicidal thoughts and actions, depression, aggression, and behavioral changes. The FDA recommended that montelukast be reserved for allergic rhinitis patients who have an inadequate response to or intolerance of alternative therapies.

For asthma, the risk-benefit calculation is different — montelukast remains a recommended option as add-on therapy, especially in children with mild persistent asthma or exercise-induced bronchoconstriction. Current GINA guidelines (2022+) recognize leukotriene receptor antagonists as an alternative controller therapy for children ≤5 years who cannot use inhaled corticosteroids reliably.

Clinical Recommendations When Patients Cannot Fill Montelukast

When a patient calls unable to fill montelukast, consider the following clinical pathway:

For Patients With Allergic Rhinitis Only

First choice: Intranasal corticosteroid (fluticasone, budesonide, triamcinolone, mometasone) — considered more effective than montelukast for nasal symptoms; all available OTC

Second choice: Second-generation antihistamine (loratadine, cetirizine, fexofenadine) — OTC; appropriate for mild-to-moderate symptoms

Combination therapy: Intranasal corticosteroid + antihistamine provides additive benefit for moderate-to-severe allergic rhinitis

For Patients With Asthma (With or Without Allergic Rhinitis)

Mild persistent asthma: Low-dose inhaled corticosteroid (ICS) is the preferred controller. If the patient cannot use an inhaler (e.g., young child with poor technique), consider zafirlukast (Accolate) as a temporary LTRA substitute — available for ages 5+.

Exercise-induced bronchoconstriction: A short-acting beta-agonist (albuterol) taken 15–30 minutes before exercise remains the first-line rescue strategy. Montelukast is an add-on controller for EIB, not the only option.

Moderate-to-severe persistent asthma: ICS or ICS-LABA combination is the appropriate controller regardless of montelukast availability.

Alternative LTRAs: Zafirlukast (Accolate) vs. Zileuton (Zyflo)

If a patient specifically requires an oral LTRA and cannot fill montelukast:

Zafirlukast (Accolate): Approved for asthma in patients ≥5 years. Dosed 20 mg BID, taken on empty stomach. Caution in hepatic impairment. Less convenient than once-daily montelukast but same drug class.

Zileuton CR (Zyflo CR): Leukotriene synthesis inhibitor. BID dosing. Approved for adults and teens ≥12 years. Requires LFT monitoring. Use when other LTRAs are contraindicated or have failed.

Counseling Patients on the Black Box Warning

Prescribers should document that neuropsychiatric risk counseling was provided at initiation of montelukast therapy. Key counseling points:

Advise patients and caregivers to discontinue montelukast and contact their provider immediately if mood or behavioral changes occur.

Take a brief psychiatric history before prescribing, especially in pediatric patients and adolescents.

For allergic rhinitis, evaluate whether first-line alternatives (intranasal steroids, antihistamines) would adequately control symptoms before initiating montelukast.

How medfinder Supports Your Patients

Rather than spending your staff's time calling pharmacies on a patient's behalf, refer them to medfinder for providers. medfinder contacts pharmacies near the patient to identify which ones can fill the prescription, then texts the patient the results. See the montelukast shortage update for the latest patient-facing information you can share directly.