Veterinary drug · Drug monograph

Pentoxifylline: veterinary dose and monograph

Pentoxifylline is a veterinary drug. Methylxanthine that improves red-cell deformability and microcirculatory flow and suppresses TNF-α and other cytokines. Indications include vasculitis, dermatomyositis, ear-margin necrosis, erythema multiforme (dogs); atopic dermatitis adjunct (dogs); endotoxaemia, cutaneous vasculitis, placentitis (horses). This monograph lists 7 reference doses for dogs, cats and horses, each with route, frequency and source.

At a glance

Drug class: Veterinary drug
Also known as: Trental, Pentoxiphylline, Oxpentifylline
Species with doses: Dogs, Cats and Horses
General dose range: 10–25 mg/kg PO q8–12h — check the species tables for the indication
Routes: PO, IV
Last reviewed: 1 October 2026

Indications

Vasculitis, dermatomyositis, ear-margin necrosis, erythema multiforme (dogs)
Atopic dermatitis adjunct (dogs)
Endotoxaemia, cutaneous vasculitis, placentitis (horses)

Pentoxifylline dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

Pentoxifylline doses for dogs
Indication	Dose	Route	Frequency	Duration
Vasculitis / ischaemic dermatopathy	10–15 mg/kg	PO	q8–12h (with food)	—
Familial dermatomyositis	25 mg/kg	PO	q12h	—
Atopic dermatitis (adjunct)	10–25 mg/kg	PO	q8–12h	—

Vasculitis / ischaemic dermatopathy: Papich 5e: dermatological use 10 mg/kg q12h, up to 15 mg/kg q8h; other uses 10–15 mg/kg q8h or 400 mg per dog. Plumb’s p.956: 10 mg/kg q8h, increasing to 15 mg/kg q8h if needed (Merchant; Boord; Hillier); 10–30 mg/kg q12h (Campbell); chronic pyoderma 20–30 mg/kg q12h (Rosenkrantz).
Familial dermatomyositis: Papich 5e and Plumb’s p.956 (Rees & Boothe 2003): 25 mg/kg PO q12h.
Atopic dermatitis (adjunct): Plumb’s p.956: 10–25 mg/kg with food two to three times daily (Yu); 10–15 mg/kg q8–12h for a 6–8 week trial (White).

Cats

Pentoxifylline doses for cats
Indication	Dose	Route	Frequency	Duration
Vasculitis / dermatological use	100 mg per cat (¼ of a 400 mg tablet) PO q8–12h	PO	q8–12h	—

Vasculitis / dermatological use: Papich 5e. Splitting extended-release tablets alters release — compounding may be preferable.

Horses

Pentoxifylline doses for horses
Indication	Dose	Route	Frequency	Duration
Vasculitis / endotoxaemia / placentitis	7.5–10 mg/kg	PO	q8–12h	—
Endotoxaemia / GI thrombosis (IV)	7.5–8.5 mg/kg	IV	q8–12h	—
Recurrent airway obstruction	36 mg/kg	PO	q12h	—

Vasculitis / endotoxaemia / placentitis: Papich 5e: 10 mg/kg q8h PO (absorption unpredictable). Plumb’s p.956: 10 mg/kg q12h, raising to 15 mg/kg q12h or 10 mg/kg q8h if efficacy wanes (Liska — cutaneous vasculitis); endotoxaemia 7.5 mg/kg q12h (Smith) or 8 mg/kg q8h (Barton); placentitis 7.5 mg/kg q12h (Troedsson). Tablets may be crushed into molasses. ARCI Class 4.
Endotoxaemia / GI thrombosis (IV): Papich 5e: 8.5 mg/kg q8h IV. Plumb’s p.956: 7.5 mg/kg IV q12h (filtered; Divers); septic foals 7.5 mg/kg IV bolus then 1.5 mg/kg/h CRI (experimental; McKenzie). No commercial injectable — prepared from tablets.
Recurrent airway obstruction: Papich 5e: respiratory disease (airway obstruction) 36 mg/kg q12h PO.

Contraindications

Recent haemorrhage (retinal/cerebral) or bleeding disorders; hypersensitivity to methylxanthines.

Adverse effects

Vomiting, GI upset (give with food)
Excitement/restlessness at high doses

Formulations and products

400 mg extended-release tablet

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Frequently asked questions

What is the dose of Pentoxifylline for dogs?

Reference doses for Pentoxifylline in dogs: 10–15 mg/kg PO q8–12h (with food) (Vasculitis / ischaemic dermatopathy); 25 mg/kg PO q12h (Familial dermatomyositis); 10–25 mg/kg PO q8–12h (Atopic dermatitis (adjunct)). Confirm against the label and the patient before use.

What is the dose of Pentoxifylline for cats?

Reference doses for Pentoxifylline in cats: 100 mg per cat (¼ of a 400 mg tablet) PO q8–12h PO q8–12h (Vasculitis / dermatological use). Confirm against the label and the patient before use.

What is the dose of Pentoxifylline for horses?

Reference doses for Pentoxifylline in horses: 7.5–10 mg/kg PO q8–12h (Vasculitis / endotoxaemia / placentitis); 7.5–8.5 mg/kg IV q8–12h (Endotoxaemia / GI thrombosis (IV)); 36 mg/kg PO q12h (Recurrent airway obstruction). Confirm against the label and the patient before use.

When should Pentoxifylline not be used?