Does metamizol (dipyrone, Novalgin) affect the inhibition of platelet function by low-dose aspirin? Observational study in patients receiving analgesic treatment of chronic pain.

Does metamizol (dipyrone, Novalgin) affect the inhibition of platelet function by low-dose aspirin? Observational study in patients receiving analgesic treatment of chronic pain. - MAI

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

DRKS

Registry ID

DRKS00000204

Enrollment

Registered

2010-03-04

Start date

2009-09-11

Completion date

Unknown

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

I25 I67.2 I70.9

Interventions

Group 1: Patients received aspirin and metamizol. Group 2: Control-group: Patients received only aspirin.

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Inclusion criteria

Inclusion criteria: Minimum age: 18 years; Cardiovascular disease with an increased risk of "atherothrombotic" events; Treatment with low-dosed acetylsalicylic acid (75-150mg/day); Duration of preceeding intake of aspirin: at least 7 days; Patients receiving an analgesic treatment with metamizol (dosage: 10-20mg/kg KG, 2-4 times per day)

Exclusion criteria

Exclusion criteria: In the preceding period of 7 days acute administration of aspirin at dosages of >150mg; Concurrent treatment with other NSAIDs (e.g. diclofenac); Additional treatment with other platelet function inhibitors (e.g. clopidogrel); Treatment with anticoagulants (e.g. vitamin K antagonists, heparin) in therapeutic dosage; Accompanying diseases which lead to relevant alterations of platelet function or haemostasis

Design outcomes

Primary

Measure	Time frame
Measurement of thrombocyteaggregation, thromboxansynthesis and metamizolconcentration in plasma during the therapy with the following methods. 1.Wholeblood-Aggregation 2.Centrifugation to gain platelet rich plasma (PRP) 3.Aggregation of PRP 4.Centrifugation to gain platelet poor plasma (PPP) 5.in case of totally abolished aggregation washing of platelets to remove dipyrone 6.Determination of thromboxane formation by radioimmunoassay (RIA) 7.Measuring of patients' plasmaconcentration of dipyrone	—

Measure

Time frame

Measurement of thrombocyteaggregation, thromboxansynthesis and metamizolconcentration in plasma during the therapy with the following methods. 1.Wholeblood-Aggregation 2.Centrifugation to gain platelet rich plasma (PRP) 3.Aggregation of PRP 4.Centrifugation to gain platelet poor plasma (PPP) 5.in case of totally abolished aggregation washing of platelets to remove dipyrone 6.Determination of thromboxane formation by radioimmunoassay (RIA) 7.Measuring of patients' plasmaconcentration of dipyrone

—

Countries

Germany

Contacts

Public ContactAndrea Schmitz

Klinik für Anästhesiologie Universitätsklinikum Düsseldorf

a.schmitz@med.uni-duesseldorf.de0211-81-16157

Outcome results

None listed

Source: DRKS (via WHO ICTRP) · Data processed: Aug 9, 2026