Zyrtec Dose for Dogs by Weight: Vet-Approved Guide (2025)

The safe Zyrtec dose for dogs is 0.5 mg per pound of body weight, given once daily, but this standard guideline only tells part of the story. A 20-pound dog typically receives 10 mg once daily, while a 50-pound dog needs around 25 mg, with a maximum daily limit of 20 mg even for large breeds. However, the exact dosage depends on your dog’s specific allergy type, severity of symptoms, underlying health conditions, and whether they’re taking other medications.

I’ve worked with hundreds of dogs suffering from seasonal allergies, atopic dermatitis, and environmental sensitivities over the past decade. While Zyrtec (cetirizine) can provide remarkable relief for itching and inflammation, I’ve also seen well-meaning owners make critical dosing errors that either render the medication ineffective or cause unnecessary side effects. The difference between helping your dog and creating new problems often comes down to understanding the nuances beyond basic weight calculations.

Why Your Vet’s Zyrtec Recommendation Might Differ From the Standard Chart

Individual Health Factors Trump Generic Guidelines

Veterinarians don’t simply pull out a generic weight chart when prescribing Zyrtec because your dog’s individual situation matters far more than a one-size-fits-all formula. A Golden Retriever with mild seasonal pollen allergies needs a completely different approach than a French Bulldog with severe atopic dermatitis and concurrent skin infections.

The standard 0.5 mg per pound guideline comes from the Merck Veterinary Manual and represents a conservative starting point for most dogs. However, veterinary dermatology research shows that some dogs with moderate to severe allergies may benefit from dosages up to 0.75 mg per pound, while others respond perfectly to lower doses given every other day. This variability exists because individual dogs metabolize cetirizine at different rates, and their histamine response patterns vary significantly.

Pre-Existing Conditions That Change Everything

Your veterinarian considers factors that no dosage chart can account for. Dogs with kidney disease process Zyrtec more slowly, potentially requiring reduced doses to prevent accumulation. Senior dogs often need conservative dosing due to age-related organ changes. Puppies under six months metabolize medications differently than adults, making standard dosing potentially dangerous. Additionally, certain breeds like Collies and other herding dogs may have genetic sensitivities that affect how they process antihistamines.

Timing and Drug Interactions Matter Too

The timing of administration also influences effectiveness. Some veterinarians recommend giving Zyrtec in the morning for dogs with daytime environmental allergies, while others suggest evening doses for dogs whose symptoms worsen at night. Dogs taking multiple medications may need adjusted timing to prevent interactions, even though Zyrtec has relatively few drug conflicts compared to first-generation antihistamines.

The Critical Difference Between Zyrtec and Zyrtec-D That Could Kill Your Dog

Why Zyrtec-D Is a Deadly Mistake

The single most dangerous mistake dog owners make with Zyrtec involves accidentally purchasing Zyrtec-D instead of plain cetirizine. This error has resulted in emergency veterinary visits, intensive care admissions, and tragically, some preventable deaths. The “D” in Zyrtec-D stands for decongestant, specifically pseudoephedrine, which is highly toxic to dogs even in small amounts.

Pseudoephedrine acts as a powerful stimulant in dogs, causing rapid heart rate increases, dangerous blood pressure elevation, tremors, seizures, and potentially fatal cardiovascular events. A single Zyrtec-D tablet contains enough pseudoephedrine to cause serious harm to a medium-sized dog and potentially kill a small dog. The symptoms can appear within 30 minutes to two hours after ingestion and require immediate emergency veterinary intervention.

The Packaging Trap That Catches Even Careful Owners

This mistake happens more often than you’d think because Zyrtec-D packaging looks remarkably similar to regular Zyrtec on store shelves. Both products come in similar boxes with comparable colors and branding. Stressed pet owners shopping quickly for allergy relief sometimes grab the wrong product without carefully reading the label. Some online retailers also bundle these products together in search results, creating additional confusion.

Other Dangerous Formulations to Avoid

Beyond Zyrtec-D, other dangerous formulations exist that pet owners need to avoid. Orally disintegrating Zyrtec tablets often contain xylitol, an artificial sweetener that’s extremely toxic to dogs and can cause life-threatening hypoglycemia and liver failure. Liquid children’s Zyrtec formulations may contain propylene glycol, which is toxic to cats and potentially problematic for some dogs. Combination products that include pain relievers, other antihistamines, or additional active ingredients should never be given to dogs without explicit veterinary approval.

How to Safely Purchase the Right Product

The safe approach involves always purchasing plain cetirizine tablets with no additional letters, words, or claims about congestion relief. Before giving any medication to your dog, hold the package under good lighting and read every word on the front and back. The active ingredients list should show only “Cetirizine HCl” or “Cetirizine Hydrochloride” with no other active compounds listed.

The Weight-Based Dosage Chart That Saves Time and Prevents Errors

Small Dogs Under 10 Pounds

Understanding proper weight-based dosing helps you have informed conversations with your veterinarian and ensures accurate medication administration at home. These guidelines reflect current veterinary standards and clinical experience, though your veterinarian may adjust based on your dog’s specific needs.

For dogs under 10 pounds, the typical dose is 2.5 to 5 mg once daily. Small breed dogs in this category include Chihuahuas, Yorkies, and toy breeds. Because standard Zyrtec tablets come in 10 mg sizes, administering accurate doses to tiny dogs often requires liquid formulations or carefully split tablets. Liquid cetirizine designed for children (1 mg per ml) makes dosing small dogs much more precise and reduces the risk of accidental overdosing.

Dogs Weighing 10 to 20 Pounds

Dogs weighing 10 to 20 pounds typically receive 5 to 10 mg once daily. This category includes small terriers, Shih Tzus, and Pomeranians. Half of a 10 mg tablet works well for dogs at the lower end of this weight range, while dogs approaching 20 pounds may need the full 10 mg tablet. The key involves starting at the lower end of the range and increasing only if symptoms don’t improve after three to five days of consistent dosing.

Medium Dogs Weighing 20 to 50 Pounds

Medium-sized dogs weighing 20 to 50 pounds generally receive 10 to 20 mg once daily. This broad category encompasses Beagles, Cocker Spaniels, Border Collies, and similar breeds. A 25-pound dog typically does well with 10 mg daily, while a 45-pound dog might need closer to 20 mg. Many veterinarians start these dogs on one 10 mg tablet daily and increase to 20 mg only if the initial dose proves insufficient after a week of treatment.

Large Dogs Weighing 50 to 80 Pounds

Large dogs weighing 50 to 80 pounds typically receive 20 mg once daily, though some veterinarians split this into two 10 mg doses given 12 hours apart. This category includes Labrador Retrievers, Golden Retrievers, and German Shepherds. Despite these dogs weighing significantly more than 40 pounds, the maximum recommended daily dose remains 20 mg due to safety considerations and diminishing returns at higher doses.

Giant Breeds Over 80 Pounds

Giant breed dogs over 80 pounds also receive a maximum of 20 mg daily, regardless of their actual weight. This applies to Great Danes, Mastiffs, Saint Bernards, and other large breeds. While the math might suggest these dogs need 40 mg or more based on the 0.5 mg per pound formula, veterinary research hasn’t established safety for higher doses, and clinical experience shows that 20 mg provides adequate relief for most dogs when combined with other allergy management strategies.

When Once Daily Isn’t Enough: Understanding Twice-Daily Dosing

The Science Behind Split Dosing

Some dogs with severe or persistent allergy symptoms benefit from splitting their daily Zyrtec dose into two administrations given approximately 12 hours apart. This approach maintains more consistent blood levels of cetirizine throughout the day and night, potentially providing better symptom control for dogs whose allergies don’t respond adequately to once-daily dosing.

Twice-daily dosing typically involves giving half the total daily dose in the morning and half in the evening. A 40-pound dog receiving 20 mg total per day would get 10 mg at 8 AM and 10 mg at 8 PM. This schedule works particularly well for dogs with environmental allergies that worsen during specific times of day or for dogs experiencing nighttime itching that disrupts their sleep.

Which Dogs Benefit Most From Twice-Daily Dosing

Veterinarians most commonly recommend twice-daily dosing for dogs with moderate to severe atopic dermatitis who haven’t achieved adequate relief with once-daily administration. The research supporting this approach comes from studies showing that cetirizine’s antihistamine effects peak within one to two hours after administration but gradually decline over the following 12 to 24 hours. By dosing twice daily, you minimize the periods when blood levels drop low enough for breakthrough symptoms.

When Twice Daily Isn’t Necessarily Better

However, twice-daily dosing isn’t automatically better than once-daily administration. Some dogs experience increased drowsiness or mild gastrointestinal upset when given Zyrtec twice daily, even though these side effects are less common with cetirizine than with older antihistamines. Additionally, the practical challenges of remembering two daily doses lead some pet owners to miss administrations, ultimately providing less consistent relief than reliable once-daily dosing.

How to Give Zyrtec to Dogs Who Refuse Medication

The Food Hiding Method

Even the most cooperative dogs sometimes resist taking pills, and Zyrtec’s lack of flavoring makes it less appealing than some pet medications. Over the years, I’ve discovered several reliable techniques that work for different dog personalities and preferences.

The simplest approach involves hiding the tablet in a small piece of high-value food that your dog can swallow quickly without excessive chewing. Cream cheese, peanut butter (xylitol-free only), liverwurst, and soft cheese all work well because they stick to the tablet and mask any taste. Roll the cheese or other food around the tablet to completely encase it, creating a small ball your dog can gulp down enthusiastically. Always follow the medicated treat with a plain treat to ensure your dog swallows everything and to create positive associations with medication time.

Using Commercial Pill Pockets

For dogs who skillfully spit out tablets hidden in food, pill pockets designed specifically for medication administration provide a commercial solution. These soft, hollow treats have a strong flavor that masks medications effectively, and their texture encourages dogs to swallow rather than chew. However, pill pockets contain calories that should be accounted for in your dog’s daily intake, especially for small breeds or dogs on weight management plans.

Crushing Tablets for Picky Eaters

Crushing the tablet and mixing it with a small amount of food works for some dogs, though this method has limitations. Zyrtec tablets can be safely crushed, but the resulting powder has a slightly bitter taste that some dogs detect and refuse. If crushing tablets, mix the powder thoroughly into a teaspoon of canned dog food, baby food (chicken or turkey varieties without onion or garlic), or plain yogurt. Ensure your dog consumes the entire mixture to receive the full dose.

Liquid Formulations as an Alternative

Liquid cetirizine formulations eliminate pill-giving challenges entirely for some households. Children’s liquid Zyrtec (1 mg per ml) can be measured precisely using the included syringe or dropper and squirted directly into your dog’s mouth or mixed into food. This approach works especially well for small dogs requiring doses under 5 mg, where splitting tablets becomes impractical. However, always check the inactive ingredients list on liquid formulations, as some contain artificial sweeteners or other additives inappropriate for dogs.

The Timing Strategy That Maximizes Relief and Minimizes Side Effects

Best Times for Environmental Allergies

When you give Zyrtec can significantly impact its effectiveness and your dog’s comfort level, yet many pet owners never receive guidance about optimal timing. Strategic scheduling helps maximize the medication’s benefits while reducing the likelihood of side effects.

For dogs with seasonal environmental allergies, giving Zyrtec in the morning before outdoor activities makes the most sense. The medication reaches peak blood levels within one to two hours of administration, providing maximum protection during peak pollen hours when your dog spends time outside. Morning dosing also allows you to monitor your dog during the day for any unexpected reactions, especially when first starting the medication.

Evening Dosing for Nighttime Itching

Dogs experiencing nighttime itching that disrupts their sleep often benefit more from evening doses given about an hour before bedtime. While cetirizine is less sedating than first-generation antihistamines, some dogs do experience mild drowsiness that can actually help them sleep more comfortably when they’re not constantly scratching. Evening dosing ensures peak medication levels occur during the overnight hours when many dogs experience the worst allergy symptoms.

Giving Zyrtec With or Without Food

The relationship between Zyrtec and food deserves consideration, though it’s less critical than with some other medications. Cetirizine can be given with or without food without affecting absorption or effectiveness. However, some dogs experience mild nausea or increased salivation when taking Zyrtec on an empty stomach. If your dog shows these signs, giving the medication with a small meal or treat usually resolves the issue completely.

Coordinating With Other Medications

For dogs taking multiple medications, spacing Zyrtec appropriately prevents potential interactions and improves treatment success. Although cetirizine has relatively few drug interactions compared to many medications, giving it at a different time than other antihistamines, sedatives, or central nervous system depressants reduces the chance of additive drowsiness effects. Your veterinarian can provide specific timing recommendations based on your dog’s complete medication regimen.

Why Consistency Matters More Than Clock Time

Consistency matters more than the exact time you choose. Dogs’ bodies respond better to medications given at roughly the same time each day, establishing predictable blood level patterns that provide more stable symptom control. Setting a daily alarm on your phone helps maintain consistency, especially during busy weeks when routines get disrupted.

Signs Your Dog’s Zyrtec Dose Needs Adjustment

Warning Signs of Insufficient Dosing

Recognizing when the current dosage isn’t working optimally allows you to work with your veterinarian to fine-tune treatment before your dog suffers unnecessarily. Both underdosing and overdosing create specific signs that observant pet owners can identify.

Insufficient dosing typically manifests as persistent allergy symptoms despite consistent medication administration. Your dog continues scratching excessively, especially around the face, paws, ears, or belly. Red, inflamed skin persists or worsens. Hair loss develops in areas of constant scratching or rubbing. Hot spots appear as your dog traumatizes their skin trying to relieve itching. These ongoing symptoms after five to seven days of consistent Zyrtec use suggest the current dose isn’t adequate for your dog’s allergy severity.

Other Factors That Mimic Underdosing

However, before assuming your dog needs more Zyrtec, consider whether other factors might be interfering with treatment success. Environmental allergen exposure might be higher than the medication can control alone. Secondary skin infections caused by constant scratching require antibiotic treatment in addition to antihistamines. Food allergies or other non-histamine-mediated conditions won’t respond to Zyrtec regardless of dosage. Your veterinarian can help determine whether dose adjustment, combination therapy, or alternative treatments make the most sense.

Signs Your Dog Is Getting Too Much

Overdosing, though less common, creates its own set of concerning signs. Excessive drowsiness or lethargy that seems unusual for your dog warrants attention. While cetirizine causes less drowsiness than older antihistamines, some dogs are more sensitive to its mild sedative effects. Vomiting, increased salivation, or mild diarrhea occasionally occur with doses at the higher end of the therapeutic range. These gastrointestinal signs typically appear within a few hours of administration and resolve on their own but suggest the dose might be more than your dog needs.

Behavioral Changes That Need Attention

Behavioral changes sometimes indicate dosing issues, though they’re more subtle. Some dogs become uncharacteristically anxious or restless on Zyrtec, while others seem confused or disoriented. These reactions are rare but warrant immediate veterinary consultation and dose adjustment or discontinuation. Difficulty urinating or signs of urinary retention represent serious side effects requiring emergency veterinary attention.

Common Mistakes That Make Zyrtec Less Effective

The Inconsistent Dosing Problem

Even when using the correct dose, certain errors reduce Zyrtec’s effectiveness or create unnecessary problems. Understanding these common pitfalls helps you maximize your dog’s treatment success.

The biggest mistake involves inconsistent dosing schedules. Skipping doses or administering medication at wildly varying times prevents stable blood levels from developing. Antihistamines work best when given consistently at approximately the same time each day, allowing your dog’s system to maintain steady protection against histamine-mediated allergic responses. Pet owners who forget doses frequently often conclude Zyrtec doesn’t work for their dog when the real issue is inadequate medication compliance.

Expecting Instant Miracles

Expecting immediate dramatic results sets up disappointment and premature medication discontinuation. Unlike emergency allergy medications that work within minutes, Zyrtec builds gradually in your dog’s system. Most dogs show some improvement within 24 to 48 hours, but optimal results often take five to seven days of consistent dosing. Some dogs with severe chronic allergies need two full weeks before achieving maximum benefit. Abandoning treatment after two days because you don’t see dramatic changes prevents the medication from demonstrating its actual effectiveness.

Relying on Zyrtec Alone

Using Zyrtec as the sole treatment for complex allergy conditions represents another common error. While cetirizine effectively blocks histamine receptors, most dogs with significant allergies benefit from comprehensive management strategies. Regular bathing with medicated shampoos removes allergens from your dog’s coat and provides additional anti-inflammatory benefits. Environmental modifications like air purifiers, frequent bedding changes, and limiting outdoor time during peak pollen hours reduce overall allergen exposure. Omega-3 fatty acid supplements support skin barrier function and reduce inflammation through different mechanisms than antihistamines.

Ignoring Secondary Complications

Failing to address secondary complications often undermines Zyrtec’s effectiveness. Dogs with chronic allergies frequently develop secondary bacterial or yeast skin infections that cause itching independent of the original allergic trigger. These infections require specific antimicrobial treatment in addition to antihistamine therapy. Similarly, dogs who’ve been scratching for weeks or months may have damaged skin barriers that continue causing discomfort even after histamine blockade. Your veterinarian can identify these secondary issues and recommend appropriate additional treatments.

When to Stop Giving Zyrtec and Call Your Veterinarian Immediately

Allergic Reactions to the Medication Itself

Certain situations require immediate discontinuation of Zyrtec and urgent veterinary consultation. Recognizing these emergency signs can prevent serious complications and ensure your dog receives appropriate care.

Signs of allergic reaction to Zyrtec itself, though rare, require immediate attention. Facial swelling, particularly around the muzzle or eyes, indicates a potentially dangerous allergic response. Hives or welts appearing suddenly on your dog’s body suggest hypersensitivity. Difficulty breathing, excessive drooling, or collapse represent anaphylactic reactions requiring emergency veterinary intervention. These severe reactions typically occur within minutes to a few hours of administration and are more common when first starting the medication.

Neurological Warning Signs

Neurological symptoms warrant immediate veterinarian contact. Unusual weakness, difficulty walking, or loss of coordination could indicate an uncommon but serious reaction. Seizures, though extremely rare with Zyrtec, require immediate emergency care. Persistent trembling or unusual jerking movements need veterinary evaluation. Any dramatic change in consciousness level or responsiveness demands urgent attention.

Severe Gastrointestinal Problems

Gastrointestinal symptoms that persist beyond 24 hours or seem severe require veterinary assessment. While mild nausea or occasional soft stool can occur when starting Zyrtec, persistent vomiting, severe diarrhea, or complete loss of appetite indicate potential problems. Blood in vomit or stool represents a medical emergency regardless of suspected cause.

Extreme Behavioral Changes

Behavioral changes that seem extreme or out of character for your dog deserve investigation. Severe lethargy where your dog barely responds to stimuli exceeds normal antihistamine drowsiness. Extreme agitation, aggression, or anxiety that’s completely uncharacteristic could indicate an adverse reaction. Confusion, disorientation, or seeming not to recognize familiar people or places requires immediate veterinary evaluation.

Urinary Complications

Urinary problems necessitate same-day veterinary attention. Difficulty urinating, straining without producing urine, or crying while attempting to urinate could indicate urinary retention, a rare but serious potential side effect. Increased urination frequency or accidents in house-trained dogs might signal other issues needing investigation.

Zyrtec vs. Other Dog Allergy Medications: Making the Right Choice

Zyrtec vs. Benadryl

Understanding how Zyrtec compares to alternative allergy treatments helps you have informed discussions with your veterinarian about the best approach for your dog’s specific situation.

Benadryl (diphenhydramine) represents the most common alternative antihistamine for dogs. As a first-generation antihistamine, Benadryl crosses the blood-brain barrier more readily than Zyrtec, causing significantly more drowsiness. Some dogs tolerate this sedation well, while others become uncomfortably lethargic. Benadryl requires more frequent dosing, typically every eight to 12 hours compared to Zyrtec’s once-daily administration. However, Benadryl often costs less and provides faster symptom relief for acute allergic reactions. Veterinary research shows mixed results when comparing effectiveness, with some studies finding Zyrtec superior for reducing inflammation, while others show similar efficacy between the two medications.

Zyrtec vs. Apoquel

Apoquel (oclacitinib) works through a completely different mechanism than antihistamines, targeting the immune signaling pathway that triggers itching. Many veterinary dermatologists consider Apoquel more effective than Zyrtec for moderate to severe allergies, with studies showing approximately 70 to 80 percent of dogs experiencing significant improvement. However, Apoquel requires a prescription, costs significantly more than Zyrtec, and carries more potential side effects including increased infection risk. Dogs with certain health conditions or those taking specific medications cannot safely use Apoquel, making Zyrtec a necessary alternative.

Zyrtec vs. Cytopoint

Cytopoint (lokivetmab) represents an injectable biological therapy that neutralizes the itch signal protein in dogs. A single injection provides relief lasting four to eight weeks, eliminating daily medication administration. Cytopoint has an excellent safety profile with minimal side effects, but the high cost per injection makes it prohibitive for some owners. Many veterinarians recommend trying less expensive options like Zyrtec first, reserving Cytopoint for dogs who don’t respond to or can’t tolerate oral antihistamines.

Zyrtec vs. Corticosteroids

Corticosteroids like prednisone provide powerful anti-inflammatory and anti-itch effects but carry significant side effects with long-term use. Veterinarians typically reserve steroids for severe allergy flare-ups or situations where other medications prove inadequate. The goal involves using the lowest effective dose for the shortest duration possible. Some veterinarians prescribe Zyrtec alongside low-dose steroids, allowing reduced steroid dosing while maintaining symptom control.

Your Essential Questions About Zyrtec Dosing Answered

Can I give my dog Zyrtec every day long-term?

Yes, many dogs safely take Zyrtec daily for months or even years when managing chronic allergies. Unlike corticosteroids, cetirizine doesn’t cause significant organ damage or serious side effects with long-term use in most dogs. However, some veterinarians recommend periodic breaks or seasonal use when appropriate to ensure the medication remains necessary and effective. Dogs on long-term Zyrtec should receive periodic veterinary checkups to assess ongoing need and monitor for any subtle changes in health status.

How quickly should I see improvement in my dog’s symptoms?

Most dogs show some reduction in itching and scratching within 24 to 48 hours of starting Zyrtec, though maximum benefit often requires five to seven days of consistent dosing. Dogs with severe chronic allergies may need up to two weeks before experiencing optimal relief. If you see absolutely no improvement after one week of consistent correct dosing, contact your veterinarian to discuss whether Zyrtec is appropriate for your dog’s specific condition or whether alternative treatments should be considered.

Can puppies take Zyrtec safely?

Veterinarians generally consider Zyrtec safe for puppies over six months old when dosed appropriately for their weight. Puppies under six months metabolize medications differently than adult dogs, making standard dosing potentially problematic. Very young puppies rarely need antihistamines, as allergies typically develop after repeated allergen exposure over time. Always consult your veterinarian before giving Zyrtec to any puppy, as they’ll assess whether the medication is necessary and appropriate for your specific puppy’s age, size, and symptoms.

What should I do if I accidentally give my dog too much Zyrtec?

Contact your veterinarian or an animal poison control center immediately for guidance specific to your dog’s weight and the amount ingested. While cetirizine has a relatively wide safety margin, significant overdoses can cause increased drowsiness, vomiting, or other concerning symptoms. Do not induce vomiting unless specifically instructed by a veterinary professional. Monitor your dog closely for unusual symptoms and be prepared to seek emergency veterinary care if drowsiness becomes extreme or other concerning signs develop.

Can I combine Zyrtec with other allergy medications?

This depends entirely on which other medications you’re considering and requires veterinary approval. Zyrtec should never be combined with other antihistamines like Benadryl without specific veterinary instruction, as this increases side effect risks without improving effectiveness. Some veterinarians prescribe Zyrtec alongside Apoquel, cytopoint, or other allergy medications for dogs with severe allergies unresponsive to single-drug therapy. However, combining medications requires professional oversight to ensure safety and appropriate dosing adjustments.

Making Every Dose Count: Your Dog’s Path to Allergy Relief

Zyrtec represents a safe, effective tool for managing canine allergies when used correctly as part of a comprehensive treatment plan. The difference between mediocre results and excellent symptom control often comes down to precise dosing, consistent administration, and realistic expectations about what antihistamines can and cannot accomplish.

Success with Zyrtec requires patience and observation. Most dogs need several days to build adequate blood levels for optimal effectiveness. Some dogs respond dramatically to antihistamine therapy, while others show modest improvement that becomes part of a multi-faceted allergy management strategy. The dogs who benefit most from Zyrtec typically have mild to moderate environmental allergies without significant secondary complications.

Your role extends beyond simply giving medication daily. Monitor your dog’s symptoms and side effects carefully, keeping notes about what you observe. Environmental management, including regular bathing, air filtration, and limiting allergen exposure, amplifies Zyrtec’s effectiveness. Working closely with your veterinarian ensures dosing adjustments when needed and helps identify when additional or alternative treatments would serve your dog better.

Remember that every dog’s allergy situation is unique. What works perfectly for your neighbor’s Labrador might prove inadequate for your dog’s specific needs. The weight-based dosing guidelines provided here offer starting points, but optimal treatment requires individualization based on your dog’s response, tolerability, and specific allergy triggers. Maintaining open communication with your veterinarian and staying observant about your dog’s symptoms ensures the best possible outcome from Zyrtec therapy.