CONTEXTElevated blood levels of lidocaine and ropivacaine have been described after transversus abdominis plane (TAP) block. OBJECTIVETo investigate the pharmacokinetic profile of ropivacaine after bilateral TAP blocks. DESIGNProspective observational pharmacokinetic study. SETTINGUniversity teaching hospital in Copenhagen, Denmark. PATIENTSTwenty-one adult patients presenting for abdominopelvic surgery with bilateral TAP blocks were enrolled. PROCEDURESUltrasound-guided TAP blocks with bilateral injections of 20 ml ropivacaine 0.5% w/v (total dose 200 mg). Blood was sampled at 0, 10, 30 and 60 min after TAP blocks. MEASURESTotal and free peak blood concentrations (Cmax) of ropivacaine. RESULTSData were analysed from N = 18 patients. The median dose of ropivacaine was 2.7 mg kg (range1.9–4.2 mg kg). Median total ropivacaine concentrations were 1.0, 1.6 and 1.7 μg ml at 10, 30 and 60 min, respectively. Six patients (33%) had Cmax values above 2.2 μg ml and the highest concentration measured was 5.1 μg ml. One patient had a 33% drop in mean arterial blood pressure. CONCLUSIONTAP blocks with bilateral injections of 20 ml ropivacaine 0.5% w/v gave rise to potentially toxic peak blood concentrations of total ropivacaine in one-third of the patients.