What is Benadryl (Diphenhydramine)

Benadryl is the brand name for one antihistamine consist of of diphenhydramine as the energetic ingredient. That is mainly prescribed to treat itching as result of insect bites, bee stings or allergies, as well as for motion sickness, take trip anxiety, sneeze (congestion), and sneezing <4, 2, 6>. It might sometimes be prescribed to regulate feline asthma.

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Can friend safely offer a cat Benadryl

Although no approved by the FDA for usage in cats <4>, veterinarians might prescribe Benadryl in an extremely low doses. Yet it is never recommended to provide Benadryl to her cat uneven prescribed by a vet.

Quick Information


Benadryl for Cats

Generic Name


Brand Name




Who can take it

Humans, cats, dogs

FDA Approved

Not for usage in pets <1>


Over-the-counter <2>

Available forms

Tablets, capsules, suspension liquid, injection

How go Benadryl work-related in cats

When over there is an allergic reaction, a chemical known as histamine is released, i m sorry travels v the body searching for histamine receptor to bind to and cause itchiness, swelling, and also other allergic symptom <6>. Diphenhydramine, gift an antihistamine, block the effect of histamine, and also hinders its ability to bind through the receptors, therefore minimizing the level to which allergy reactions can impact the human body <4, 6>.

Benadryl dosage: how much can you give to a cat

Follow the prescription in regard to the dosage and also duration that the treatment. Varying according to the size, weight, and also age of her cat, the usually prescribed dosage is:

Oral TabletsOral LiquidIntramuscular Injection
0.25-0.50 mg/pound twice a job <6>0.4ml/pound <8> as countless times together prescribed through the vet0.50-1 mg/pound double a work <6>

The duration of the treatment depends on the problem being treated <6>.

Note: people often think about giving their cat Benadryl to calm them under for a auto ride, or because that a to organize session, specifically for cutting your nails. However, it have the right to be exceptionally hazardous to use Benadryl without medical supervision as it have the right to lead to a toxicity the can easily turn life-threatening for your pet.

What to carry out if you miss a dose

Try to carry out the missed sheep as soon as friend remember. However, if it is currently time because that the following dose, you need to skip the to let go one entirely and continue through the continual dosing schedule. The is inadvisable to give two sheep at when <2>.

Side-effects in cats

Common side results may incorporate <2>:

Drowsiness and sedationHyper-excitementDry mouthUrine retentionDiarrheaVomitingLoss that appetite

The cat may drool or foam in ~ the mouth once you offer the medication; this is typical as Benadryl tastes quite bitter to them.

What happens in case of one overdose

A Benadryl overdose can lead to significant toxicity in a cat, causing seizures, troubled breathing, coma, and also even death. Automatically get in touch v the vet or the ASPCA animal Poison Control facility Helpline (1-888-426-4435).

There is a basic misconception the Benadryl have the right to be supplied to euthanize a cat, but it is no recommended together the suffering it would cause to the feline will certainly make the a fairly inhumane way to put down a pet.

Contraindications: when not to give

It is commonly not given to cats enduring from <2, 6>:

Heart diseasesHypertension (High blood pressure)HyperthyroidismBladder disordersGlaucoma

The medicine is usually not prescribed come pregnant and also nursing cats.

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Inform the vet about any medications your cat can be getting; Benadryl is well-known to connect with the following drugs <2>:

EpinephrineSelegilineFurazolidonWarfarin sodiumHeparin calcium or sodiumAmitrazCentral Nervous device depressants

Fexofenadine (Allegra), cetrizine (Zyrtec), loratadine (Claritine), and dimenhydrinate (Dramamine) are often taken into consideration as choices to diphenhydramine; but it is recommended to inspect with the vet before going for any kind of of those.