Alternatives to Montelukast If You Can't Fill Your Prescription

Montelukast (generic Singulair) is a widely used leukotriene receptor antagonist for asthma and allergic rhinitis. But what happens when you can't get it filled? Whether your pharmacy is temporarily out of stock or you're experiencing intolerable side effects, knowing your alternatives means you're never left without a plan.

This guide covers the most clinically relevant alternatives to montelukast — organized by use case (asthma vs. allergic rhinitis) and sorted from most to least commonly recommended.

Important: Always Talk to Your Prescriber Before Switching

Montelukast treats two different conditions (asthma and allergic rhinitis), and the best alternative depends on which condition you're treating. Some alternatives are appropriate for both; others are only for allergies. Your doctor or NP is the right person to guide this decision — don't stop montelukast abruptly for asthma without guidance.

Alternatives for Allergic Rhinitis (Hay Fever)

For allergic rhinitis, the FDA actually recommends that montelukast should only be used when other therapies haven't worked, due to its black box warning for neuropsychiatric effects. That means most of these alternatives are actually preferred over montelukast for allergies alone:

1. Nasal Corticosteroid Sprays (Strongest First-Line Option)

Nasal corticosteroid sprays are considered the most effective treatment for allergic rhinitis. They reduce inflammation directly in the nasal passages and are available over the counter.

Fluticasone (Flonase Allergy Relief) — OTC; once daily; among the most effective nasal sprays available

Budesonide (Rhinocort) — OTC; once daily; safe for pregnancy

Triamcinolone (Nasacort) — OTC; effective for nasal and sinus congestion

Studies show nasal corticosteroids are more effective than montelukast at reducing nasal symptoms. They do not treat asthma, however.

2. Second-Generation Antihistamines (Easy OTC Option)

Antihistamines block histamine receptors to reduce sneezing, runny nose, and itching. Second-generation antihistamines are non-drowsy (or low-drowsiness) and widely available without a prescription:

Loratadine (Claritin) — OTC; non-drowsy; once daily; inexpensive

Cetirizine (Zyrtec) — OTC; once daily; slightly more potent, may cause mild drowsiness

Fexofenadine (Allegra) — OTC; twice daily; lowest drowsiness profile

Studies have shown the combination of loratadine and montelukast is more effective than either alone — so if you're already on an antihistamine, adding it back with another therapy may help bridge a supply gap.

Alternatives for Asthma

For asthma, montelukast is used as a controller medication — not a rescue medication. Stopping it abruptly may lead to worsening symptoms. Here are the most common alternatives your prescriber might recommend:

3. Inhaled Corticosteroids (ICS) — Gold Standard for Asthma

Inhaled corticosteroids are the first-line treatment for persistent asthma and are more effective than montelukast at improving lung function:

Budesonide inhaler (Pulmicort Flexhaler) — twice daily; widely used in children and adults

Fluticasone propionate inhaler (Flovent HFA) — twice daily; available in multiple strengths

Beclomethasone inhaler (Qvar RediHaler) — once or twice daily depending on dose

4. Other Leukotriene Receptor Antagonists

Two other drugs work by a similar mechanism to montelukast but differ in dosing and side effect profiles:

Zafirlukast (Accolate) — another LTRA; taken twice daily; approved for asthma in patients 5 and older; requires taking on an empty stomach

Zileuton (Zyflo CR) — a leukotriene synthesis inhibitor (blocks production rather than receptors); taken twice daily (CR) or four times daily; requires liver function monitoring; approved for adults and teens 12+

Both zafirlukast and zileuton are less convenient than once-daily montelukast, which is why they are used less frequently. But they can be good options if montelukast is temporarily unavailable.

5. Combination ICS-LABA Inhalers (for Moderate-Severe Asthma)

For patients with moderate to severe persistent asthma whose symptoms aren't controlled by montelukast alone, a combination ICS-LABA inhaler may be an appropriate next step:

Advair Diskus (fluticasone/salmeterol) — twice daily; widely prescribed

Symbicort (budesonide/formoterol) — twice daily; can also serve as rescue inhaler in some protocols

What to Tell Your Doctor

When calling your prescriber about a supply issue, be prepared to share:

Which condition you're treating (asthma, allergies, or both)

How long you've been on montelukast and how well it's worked

Any allergies or intolerances to medications you know about

Whether the difficulty is a temporary shortage (stock issue) or a longer-term access problem (insurance, cost)

Before switching medications, it's always worth trying to locate your current prescription. Check out our guide on how to find montelukast in stock near you, or let medfinder search local pharmacies on your behalf.