Introduction
Allergies to cats and dogs affect 10–20% of the population worldwide and are a growing public health concern as rates increase. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5809771/ The most common allergies in dogs are environmental allergies and food allergies, both of which can cause severe itchiness and skin irritation. Environmental allergies, also called atopic dermatitis, are often triggered by common allergens like pollen, mold, dust mites, and grass. When dogs with environmental allergies are exposed to these allergens, their immune system overreacts and causes an inflammatory reaction and itchiness. Food allergies can also cause red, irritated skin and obsessive scratching and licking in dogs. This article will compare two common medications used to treat dog allergies and itchiness – Zyrtec and Apoquel.
What is Zyrtec?
Zyrtec (cetirizine hydrochloride) is an antihistamine drug used to treat allergy symptoms such as itching, sneezing, watery eyes, and runny nose. Zyrtec works by blocking histamine, a natural substance in the body that causes allergic reactions (1). Antihistamines provide relief of allergy symptoms but do not cure the underlying allergy or prevent future reactions.
Zyrtec comes in tablet, chewable tablet, and liquid forms. It is available over-the-counter and by prescription. The standard oral dose for adults and children over 6 years old is one 10 mg tablet once per day. Zyrtec starts working within 1 hour and provides 24 hours of relief from allergy symptoms.
Common side effects of Zyrtec include drowsiness, fatigue, dry mouth, sore throat, and headache. More serious side effects are unlikely but can include difficulty urinating, fast or irregular heartbeat, and yellowing eyes or skin (2, 3).
What is Apoquel?
Apoquel (oclacitinib) is a prescription medication used to treat itching and inflammation associated with allergic skin conditions in dogs. It works by inhibiting Janus kinases (JAKs), specifically JAK1 and JAK3, which are involved in inflammatory and immune pathways in the body (Gonzales et al., 2014).
By selectively inhibiting JAK1 and JAK3, Apoquel targets the itching and inflammation caused by allergies, while having minimal effects on other immune system functions. This makes it effective for controlling the clinical signs of allergic dermatitis and other pruritic conditions in dogs (Apoquel.com).
Apoquel stops the itch-scratch cycle that leads to inflammation and damage to the skin in dogs with allergies. By providing fast relief from the urge to scratch, it can greatly improve a dog’s quality of life when used as directed by a veterinarian.
Zyrtec vs. Apoquel for Dogs
Both Zyrtec and Apoquel can be effective in controlling allergy symptoms in dogs, but they work in different ways. Apoquel is a targeted medication that specifically blocks itch-inducing chemicals called interleukins, providing fast relief from itching and inflammation caused by allergies [1]. In comparison, Zyrtec is an antihistamine that blocks the action of histamine, which is released by the immune system during an allergic reaction [2].
For most dogs with allergies, Apoquel starts working more quickly and is more effective at relieving allergy symptoms like itchy skin, rashes, and ear infections. In a clinical trial, dogs on Apoquel showed an 89% improvement in itching and inflammation within 24 hours, compared to just a 9% improvement for dogs given Zyrtec [3].
However, Apoquel only treats the symptoms of allergies, whereas Zyrtec also helps reduce the body’s allergic response. For some dogs, Zyrtec can provide adequate relief, especially when combined with other treatments like medicated baths. Zyrtec also has the advantage of fewer side effects compared to Apoquel when used long-term.
Zyrtec Dosage for Dogs
When giving Zyrtec to dogs, it’s important to administer the proper dosage based on your dog’s weight. Zyrtec dosage for dogs is typically 0.9-1.8 mg per pound given every 24 hours. Some common Zyrtec dosages based on weight are:
- Less than 10 lbs: 2.5 mg (half a 5 mg tablet)
- 10-25 lbs: 5 mg
- 26-50 lbs: 10 mg
- 51-75 lbs: 15 mg
- 76-100 lbs: 20 mg
Zyrtec tablets come in 5mg and 10mg strengths. For small dogs, you can break the tablets into halves or quarters to achieve the proper dose. It’s best to consult with your veterinarian on the ideal dosage for your individual dog. Be sure to give the dose every 24 hours consistently.
Some key things to keep in mind when dosing dogs with Zyrtec:
- Don’t exceed the recommended dosage
- Shake tablets before breaking to distribute medication evenly
- Give with food if it causes an upset stomach
- Monitor for side effects like sedation or vomiting
Following dosage guidelines carefully helps ensure your dog gets relief from allergies without negative effects. Check with your vet if you have any questions about proper Zyrtec dosage for your dog.
Apoquel Dosage for Dogs
The recommended dosage of Apoquel for dogs is 0.4-0.6 mg/kg body weight, administered orally, twice daily for up to 14 days. After initial administration, Apoquel can be continued long-term as maintenance therapy at 0.5-2 mg/kg once daily. The dosage is calculated based on the dog’s body weight.
For example, a 22 lb dog would get 3.5 mg twice daily as the initial dose. This is calculated by taking the mid-range dosage of 0.5 mg/kg and multiplying it by the dog’s weight in kg (10 kg). The maintenance dose would be 5.5 mg once daily.
Apoquel is available as 3.6 mg, 5.4 mg and 16 mg tablets. The tablets can be given directly or hidden in food. An accurate weight is important to calculate the proper dose. Owners should follow their veterinarian’s dosage instructions closely when giving Apoquel to their dog.
According to the manufacturer Zoetis [1], the dosing chart for Apoquel tablets is:
- 3.6 mg tablets: for dogs 3-7 lbs
- 5.4 mg tablets: for dogs 7-15 lbs
- 16 mg tablets: for dogs 15-122 lbs
Risks and Side Effects
Both Zyrtec and Apoquel carry potential side effects, so it’s important to monitor your dog closely when giving either medication.
Some of the more common side effects of Zyrtec in dogs include: lethargy, vomiting, diarrhea, and lack of appetite. These effects are usually mild, but can be concerning in some dogs. Zyrtec is generally very safe, even when used long-term.
Apoquel has been associated with more serious side effects in some dogs. According to the product label, possible side effects include vomiting, diarrhea, lethargy, anorexia, and unspecified skin or subcutaneous masses. There have also been rare reports of immune system suppression, seizures, and death in dogs taking Apoquel.
In general, Zyrtec is considered safer than Apoquel for long-term use. However, it’s still important to monitor your dog closely and report any concerns to your veterinarian when using either medication.
Cost Comparison
When comparing the cost of Zyrtec and Apoquel for dogs, Apoquel is significantly more expensive. According to Canine Journal, Apoquel costs around $2.43 per tablet regardless of strength. For a 45 lb dog taking two tablets per day, this equates to around $50-80 per month.
Zyrtec is available over-the-counter and is far less expensive. The typical Zyrtec dose for a 45 lb dog is 5-10 mg per day. A bottle of 100 Zyrtec 10 mg tablets costs around $13-15. This means a monthly supply of Zyrtec for a 45 lb dog costs approximately $4-5.
So while Apoquel is a prescription-only medication specially formulated for dogs, its high price point makes it less accessible. Zyrtec is a fraction of the cost at around $4-5 per month for a 45 lb dog. While not as targeted for canine allergies, Zyrtec provides a more budget-friendly option according to Grand Avenue Veterinary Clinic.
When to Give Zyrtec vs. Apoquel
Zyrtec and Apoquel are both medications used to treat itching and allergies in dogs, but they have different appropriate uses:
Zyrtec (cetirizine) is an antihistamine, so it is most effective at treating mild to moderate allergy symptoms caused by environmental allergens like pollen or dust mites. According to this source, Zyrtec can help relieve itchiness, watery eyes, sneezing, and skin irritation in dogs with seasonal or environmental allergies. It works by blocking histamine receptors.
Apoquel (oclacitinib) is a targeted immunomodulatory drug, so it is most effective for controlling constant, year-round itching and allergies. According to this source, Apoquel is often prescribed for dogs with chronic allergic dermatitis and can significantly improve their quality of life by reducing itch within 24 hours. It works by inhibiting certain pathways involved in inflammation and allergic responses.
In summary, vets may recommend Zyrtec for milder, seasonal allergy symptoms and Apoquel for more severe, chronic allergy and itch relief. Zyrtec has a faster onset but shorter duration than Apoquel. Your vet can help determine the most appropriate medication based on your dog’s specific condition and symptoms.
Conclusion
Allergies are a common problem for dogs, causing irritating symptoms like itching, scratching, and skin infections. While medications like Zyrtec and Apoquel can provide relief, it’s important to weigh the pros and cons of each when deciding which is best for your dog.
In summary, Zyrtec is an affordable over-the-counter antihistamine that can help manage mild to moderate allergy symptoms. It has a good safety profile, but may cause drowsiness. Apoquel is a prescription medication that targets itching and inflammation. It starts working more quickly than Zyrtec, but is much more expensive and has some potentially serious side effects.
When choosing between the two, consider your dog’s specific symptoms and severity of allergies. Zyrtec is usually preferred for mild seasonal allergies, while Apoquel may be better for acute flare-ups of severe itching. Always consult your vet before giving any new medication. With the proper treatment, you can help provide your dog relief and let them live their best life.