UK Clinical Pharmacy Association

Pentoxifylline

Issues for surgery

Loss of symptom control if omitted.

Potential for increased risk of bleeding if continued – see Further information.

Advice in the perioperative period

Elective and emergency surgery 

Continue.

Post-operative advice

Restart post-operatively once enteral intake resumed.

Monitor renal function post-operatively. Dose reduction may be necessary if there is post-operative renal impairment – see current product literature.

Interactions with common anaesthetic agents

None.

Interactions with other common medicines used in the perioperative period

Non-steroidal anti-inflammatory drugs (NSAIDs)

There is potentially an increased risk of bleeding and/or prolongation of prothrombin time when pentoxifylline is used concomitantly with NSAIDs (other than selective COX-2 inhibitors); monitor for signs of increased bleeding tendancies.

Ketorolac is specifically mentioned and the UK manufacturer of pentoxifylline contraindicates concomitant use.

Ciprofloxacin

Ciprofloxacin may increase serum concentrations of pentoxifylline, which may lead to an increase in pentoxifylline adverse reactions, such as severe headache.

Whilst single surgical prophylactic doses should not pose a problem, continued post-operative treatment may require close monitoring for adverse reactions; a dose reduction in pentoxifylline dose may be necessary, consult current product literature.

Cimetidine

Concomitant administration with cimetidine may increase the plasma concentration of pentoxifylline and adverse effects, such as headache and nausea, may increase with concomitant use. 

Further information

Bleeding risk

A few very rare events of bleeding have been reported in patients treated with pentoxifylline with and without anticoagulants or platelet aggregation inhibitors. The serious cases are predominantly concentrated in the gastrointestinal, genitourinary, multiple site and surgical wound areas and are associated with bleeding risk factors. A causal relationship between pentoxifylline therapy and bleeding has not been established. Thrombocytopenia has occurred in isolated cases.

References

Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 4th April 2024]

Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 4th April 2024]

Summary of Product Characteristics – Trental®(pentoxifylline)) 400 mg Modified release Tablets. Neuraxpharm UK Ltd. Accessed via www.medicines.org.uk 19/02/2024 [Date of revision of the text June 2023]