Current guidelines for the treatment of pain recommend the use of multimodal therapy. The use of polypharmacotherapy is always associated with the risk of side effects, which in their consequence may worsen the effectiveness of pain treatment and may lead to the need to discontinue the use of

Based on the observation of 60 patients in whom adverse events with different clinical picture occurred as a consequence of the use of combination therapy, were assessed what drug combinations are associated with a special risk of interaction

The clinical signs of adverse reactions with the drugs used was correlated and the causal relationship between the drugs used and the adverse effects observed was assessed. In 48 patients, there was a need to stop using combination therapy. The remaining 12 were corrected for the dosage of drugs used in polytherapy or modification of individual drugs used to treat pain

The analysis shows that the common problem we observe in combined pain therapy are pharmacokinetic interactions between co-analgesics and analgesics, both opioids and non-opioid analgesics. Due to the pharmacokinetic profile, pharmacokinetic interactions are often observed when duloxetine, venlafaxine and valproate are used. Very rarely, side effects are a consequence of treatment with pregabalin. It is also worth remembering about the increased risk of bleeding complications in patients taking simultaneously NSAIDs and duloxetine or venlafaxine, and this interaction is pharmacodynamic.

UNFAVORABLE PHARMACOKINETIC INTERACTIONS OF CO-ANALGESICS - WHICH DRUG COMBINATIONS SHOULD BE AVOIDED