Alternatives to Cetirizine if you can't fill your prescription

When Cetirizine Isn't Available: Your Options

Cetirizine (Zyrtec) is a go-to allergy medication for millions of Americans. But what happens when your pharmacy is out of stock, when Cetirizine isn't working well enough for you, or when side effects like drowsiness are getting in the way?

The good news is that several other second-generation antihistamines treat the same conditions as Cetirizine — seasonal allergies, year-round allergic rhinitis, and chronic hives (urticaria). All of the alternatives discussed here are available over the counter, and your pharmacist can help you make the switch without needing a doctor's visit.

Understanding How Cetirizine Works

Before comparing alternatives, it helps to understand what Cetirizine does. Cetirizine is a second-generation antihistamine that blocks histamine H1 receptors. When your body encounters an allergen (like pollen, dust mites, or pet dander), it releases histamine — a chemical that causes sneezing, itching, runny nose, and watery eyes. Cetirizine blocks histamine from triggering these symptoms.

All of the alternatives below work through the same basic mechanism — they block H1 receptors — but they differ in how sedating they are, how quickly they work, and how long they last. For a deeper dive, see our post on how Cetirizine works.

Alternative #1: Loratadine (Claritin)

Loratadine is probably the most well-known alternative to Cetirizine. Sold under the brand name Claritin, it's been available OTC since 2002.

• Dose: 10 mg once daily
• Onset: 1-3 hours
• Duration: 24 hours
• Sedation: Less sedating than Cetirizine — a good choice if drowsiness is a concern
• Best for: People who need an effective antihistamine without any drowsiness
• Cost: Similar to generic Cetirizine — very affordable as a generic

Key difference: Loratadine is generally considered less potent than Cetirizine for severe symptoms but causes less drowsiness. If you find that Cetirizine makes you too sleepy, Loratadine may be a better fit.

Alternative #2: Fexofenadine (Allegra)

Fexofenadine is sold under the brand name Allegra and is considered the least sedating antihistamine in its class.

• Dose: 180 mg once daily (for adults) or 60 mg twice daily
• Onset: 1-2 hours
• Duration: 24 hours
• Sedation: Very low — true non-drowsy option
• Best for: People who need to stay completely alert (drivers, students, professionals)
• Cost: Affordable as a generic; brand-name Allegra is moderately priced

Key difference: Fexofenadine should not be taken with fruit juices (orange, apple, grapefruit), which can significantly reduce absorption. Take it with water only.

Alternative #3: Levocetirizine (Xyzal)

Levocetirizine is the active isomer (mirror image) of Cetirizine. It's essentially a more refined version of the same molecule.

• Dose: 5 mg once daily
• Onset: Less than 1 hour
• Duration: 24 hours
• Sedation: Similar to Cetirizine but may be slightly less sedating at the lower dose
• Best for: People who respond well to Cetirizine but want to try a more targeted option
• Cost: Available as OTC generic; slightly more expensive than Cetirizine generics

Key difference: Because Levocetirizine is the active half of Cetirizine, you only need half the dose (5 mg vs. 10 mg) for similar effectiveness. This can mean fewer side effects for some people.

Alternative #4: Desloratadine (Clarinex)

Desloratadine is the active metabolite of Loratadine. Unlike the other options on this list, it's available by prescription only.

• Dose: 5 mg once daily
• Onset: 1-3 hours
• Duration: 24 hours
• Sedation: Very low
• Best for: People who have tried OTC options and need a prescription-strength non-sedating antihistamine
• Cost: Available as a generic; requires a prescription, which may affect out-of-pocket cost

Key difference: Desloratadine requires a prescription, so you'll need to see a doctor or use a telehealth service. It may be covered by insurance, which can offset the cost.

Other Options to Consider

Beyond oral antihistamines, you might also find relief with:

• Nasal corticosteroid sprays (Flonase, Nasacort) — available OTC, very effective for nasal congestion, which antihistamines don't treat well
• Antihistamine eye drops (Ketotifen/Zaditor) — OTC drops for itchy, watery eyes
• Combination therapy — many allergists recommend using a nasal spray alongside an oral antihistamine for comprehensive relief

How to Switch Safely

Switching between second-generation antihistamines is generally straightforward:

1. You can usually switch immediately — stop taking Cetirizine one day and start the new antihistamine the next
2. Note about rebound itching: If you've taken Cetirizine daily for months or years, stopping suddenly may cause temporary rebound itching. This is not an allergic reaction — it's a known withdrawal effect. Tapering your dose gradually over 1-2 weeks can help
3. Give the new medication time: Allow 3-7 days to assess whether the alternative works as well for you
4. Talk to your pharmacist: They can help you choose the right alternative and dose without needing a doctor's appointment

For more information about Cetirizine side effects and when to contact your doctor, see our guide: Cetirizine side effects: what to expect.

Quick Comparison Chart

Here's how the top alternatives stack up against Cetirizine:

• Cetirizine (Zyrtec): 10 mg daily, moderate sedation risk, fast onset, very effective
• Loratadine (Claritin): 10 mg daily, low sedation risk, moderate onset, effective
• Fexofenadine (Allegra): 180 mg daily, minimal sedation risk, moderate onset, effective (avoid fruit juice)
• Levocetirizine (Xyzal): 5 mg daily, moderate sedation risk, fast onset, very effective
• Desloratadine (Clarinex): 5 mg daily, low sedation risk, moderate onset, effective (Rx only)

Still Looking for Cetirizine?

If you'd rather stick with Cetirizine, use MedFinder to find pharmacies near you that have it in stock. You can also read our tips on how to find Cetirizine near you and learn about the latest Cetirizine availability updates for 2026.