# 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.

Source: https://vetmasterji.com/drugs/pentoxifylline · Last reviewed: 2026-10-01

## 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

> **Caution:** 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.

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## 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?

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

### What are the side effects of Pentoxifylline in animals?

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

## Sources

- Plumb's Veterinary Drug Handbook
- Papich 5e — Pentoxifylline
- Papich, Papich Handbook of Veterinary Drugs, 5th edition

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VetMasterJi is a clinical decision-support and education platform for veterinary professionals and students. It does not provide veterinary advice, diagnosis or treatment for specific animals. All drug doses, calculators and differentials are references that must be independently verified before clinical use; the attending registered veterinarian remains solely responsible for every clinical decision.