Sourced from published veterinary references. Awaiting credentialed clinical reviewer — our editorial process.
Diphenhydramine is dosed at 2 mg/kg PO, SC q8-12h in rabbits, per Morissey JM, Carpenter JW. Appendix: Formulary. In: Quesenberry KE, OrcuttCJ, Mans C, et al. Ferrets, Rabbits and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.877 — Carpenter's Exotic Animal Formulary 6th ed, Table 10.10 (Miscellaneous Agents Used in Rabbits). Verify against current literature before clinical use.
Competitive antagonist at histamine H1 receptors. Also has anticholinergic, anti-motion sickness, and mild sedative properties.
Side effects & warnings
Sedation common (first-generation). Anticholinergic effects (dry mouth, urinary retention). Ensure product does not contain xylitol or pseudoephedrine. Dogs and cats. Less effective than second-gen antihistamines for pruritus.
Species with Diphenhydramine dosing data (16 dose rules)
Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.
Sample dosing (2 of 16 cited rules)
A dog/cat sample is shown here. Cited dosing for all 15 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.
Plumb's 10th ed printed p.410, Diphenhydramine monograph spanning p.409-411. — Plumb's Veterinary Drug Handbook, 10th ed, Diphenhydramine monograph, printed p.410, DOGS/CATS: "Antihistamine (eg, adjunctive treatment of allergic pruritus or reactions, including angioedema […]"Compilation only — we have not located an independent source that prints this figure.
Plumb's Veterinary Drug Handbook, 10th ed (2023) — Plumb's 10th ed printed p.409, Diphenhydramine monograph spanning p.409-411.Compilation only — we have not located an independent source that prints this figure.
· 130. Morrisey JK, Carpenter JW. Formulary. In: Quesenberry KE, Carpenter JW, eds. Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.796 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.6 (Emergency Drugs Used in Rodents).
· 130. Morrisey JK, Carpenter JW. Formulary. In: Quesenberry KE, Carpenter JW, eds. Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.800 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.6 (Emergency Drugs Used in Rodents).
· 315. France M. Chemotherapy treatment of lymphosarcoma in a Moluccan cockatoo. Proc Annu Conf Assoc Avian Vet; 1993:15-19. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.490 — Carpenter's Exotic Animal Formulary 6th ed, Table 5.18 (Miscellaneous Agents Used in Birds).
· 952. van Zeeland Y. Medication for behavior modification in birds. Vet Clin North Am Exot Anim Pract. 2018;21(1):115-149. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.472 — Carpenter's Exotic Animal Formulary 6th ed, Table 5.10 (Psychotropic and Antiepileptic Agents Used in Birds.a,b).
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· Chitty JR, Johnson-Delaney CA. Emergency care. In: Johnson-Delaney CA, eds. Ferret Medicine and Surgery; CRC Press, Boca Raton, FL; 2017:113-125. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.955 — Carpenter's Exotic Animal Formulary 6th ed, Table 11.10 (Miscellaneous Agents Used in Ferrets.a).
· Meredith A. BSAVA Small Animal Formulary: Part B: Exotic Pets, British Small Animal Veterinary Association, Quedgeley, Gloucester, UK; 2015. / Morrisey JK, Carpenter JW. Formulary. In: Quesenberry KE, Carpenter JW, eds. Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.796 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.6 (Emergency Drugs Used in Rodents).
· Morissey JM, Carpenter JW. Appendix: Formulary. In: Quesenberry KE, OrcuttCJ, Mans C, et al. Ferrets, Rabbits and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.877 — Carpenter's Exotic Animal Formulary 6th ed, Table 10.10 (Miscellaneous Agents Used in Rabbits).
· Morrisey JK, Carpenter JW. Formulary. In: Quesenberry KE, Carpenter JW, eds. Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.796 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.6 (Emergency Drugs Used in Rodents).
· Morrisey JK, Carpenter JW. Formulary. In: Quesenberry KE, Carpenter JW, eds. Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.800 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.6 (Emergency Drugs Used in Rodents).
· Morrisey JK, Carpenter JW. Formulary. In: Quesenberry KE, Carpenter JW, eds. Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery, 4th ed., Elsevier, St. Louis, MO; 2021:620-630. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.800 — Carpenter's Exotic Animal Formulary 6th ed, Table 9.7 (Miscellaneous Agents Used in Rodents).
· Plumb's 10th ed printed p.410, Diphenhydramine monograph spanning p.409-411.
· Plumb's 10th ed printed p.410, Diphenhydramine monograph spanning p.409-411. — Plumb's Veterinary Drug Handbook, 10th ed, Diphenhydramine monograph, printed p.410, DOGS/CATS: "Antihistamine (eg, adjunctive treatment of allergic pruritus or reactions, including angioedema […]"
· Plumb's Veterinary Drug Handbook, 10th ed (2023) — Plumb's 10th ed printed p.409, Diphenhydramine monograph spanning p.409-411.
· Starkey SR, Morrisey JK, Hickam JD, et al. Extrapyramidal side effects in a blue and gold macaw (Ara ararauna) treated with haloperidol and clomipramine. J Avian Med Surg. 2008;22:234-239. — Source: Carpenter's Exotic Animal Formulary, 6th Ed, p.472 doi:10.1647/2007-037.1 — Carpenter's Exotic Animal Formulary 6th ed, Table 5.10 (Psychotropic and Antiepileptic Agents Used in Birds.a,b).
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