Quick FAQ: PRP while on Aspirin or Plavix
Is it ok to do PRP with Aspirin, ASAS, Plavix or other medication?
Yes, PRP treatments could be taken while on anti-platelet medication such as aspirin, ASA or Plavix (clopidogrel). However, this is an area where more research needs to be done. While some studies show a lower release of growth factors in the presence of PRP, other studies show that the number of growth factors is not significantly affected.
Will PRP work if I’m taking ASA or Plavix?
Maybe. The evidence is not really clear. We know from physiology that ASA interferes with platelet function. For this reason, some experts recommend against using PRP treatments when a patient is taking anti-platelet medication. But there have also been limited reports that PRP still works. For example, a male runner in his 50s taking both ASA and Plavix had benefit from a PRP joint injection.
Is there any risk to having PRP treatments while on ASA or Plavix?
PRP is very safe and there does not seem to be any increased risk to PRP treatments while on aspirin or Plavix. In fact, the only reported negative effect associated with doing this was related to stopping ASA prior to getting a PRP treatment. In other words, it was not caused by the PRP but by the patient stopping his aspirin without telling his doctor.
Should I stop ASA, aspirin or Plavix prior to getting PRP?
NO. As mentioned above, this could have disastrous consequences. You should never stop any medication without consulting your doctor. ASA and Plavix are prescribed to prevent cardiovascular complications such as stroke and heart attack and should never be stopped without clear instructions from your doctor.
What the research says about PRP and anti-platelet medication such as Aspirin or Plavix
ASA (Aspirin) and Plavix (clopidogrel) are two very common and important anti-platelet medications used to reduce the risk of cardiovascular disease. They are effective and taken by many patients. As platelet-rich plasma, PRP treatments are growing in awareness and popularity for a number of conditions, the question of whether these medications could affect PRP treatments is becoming very relevant.
The Most Important Message
The most important thing to remember if you are taking ASA, Plavix or some other medication and considering PRP treatment is
Do not stop taking any medication without consulting your doctor first.
Stopping aspirin or plavix could lead to serious unwanted consequences like stroke or heart attack. This actually happened to one patient who stopped his ASA prior to getting a PRP treatment without telling his doctor.1
What we know: ASA interferes with PRP activation
Platelet activation is a complicated process (see diagram) with many pathways. One of these involves cyclooxygenase 1 (COX-1)-mediated conversion of arachidonic acid (AA) to trigger growth factor release.2,3Aspirin blocks COX-1 irreversibly, which is why some authors have suggested that it should be stopped for 7 days prior to PRP injections as the lifespan of platelets is about 8-9 days so this would give the body time to generate platelets that have not been affected by ASA.4
Due to the known inhibitory effects of antiplatelet medications like ASA and Plavix, some experts recommend against using PRP in these situations. But..
A case report of benefit:
A group of Italian doctors reported the case of a 52 year old male competitive runner who had such severe knee pain that he had to stop his running altogether. MRI showed severe osteoarthritis in the knee but he was not a candidate for surgery and due to his high risk for cardiovascular disease (due to a genetic disorder), he could not stop his ASA or Plavix.
He has previously tried several conservative treatments, such as physiotherapy, TENS, hyaluronic acid (Synvisc), magnetotherapy, etc. without any significant benefit. The patient, understanding that PRP quality may be affected by the ASA and Plavix, elected to go ahead. He received three injections of activated PRP, one week apart and the results were dramatic. After one week, he gradually resumed physical activity. By 14 days after the PRP treatment, he was pain-free and started training again. He was able to complete the Bologna City Half-Marathon only 35 days after his treatment. 5
While this sounds amazing, it is important to remember that it’s only one case report and certainly does not constitute enough evidence to make a recommendation for the general patient population. There are many other patients who received PRP injections for knee arthritis who did not improve. Nevertheless, it is an encouraging story.
The research shows mixed results
To be sure, the research on this topic is a bit mixed, showing no clear answer. A recent systematic review in the Orthopaedic Journal of Sports Medicine looked at 15 studies published over the past 25 years. Seven of the studies detected no significant decrease in growth factors whereas six did show a decrease with antiplatelet agents.6
Making sense of the discrepency
Why did some studies show that antiplatelet medication interfered with PRP while others did not?7 PRP is a complex physiological process. There are many pathways involved in platelet activation and the release of growth factors.2 There are multiple other pathways of platelet activation. These pathways are targeted in different ways depending on the method of PRP preparation and injection which probably explains the varying results reported in the research to date.
Preparing PRP is a delicate process with many variables. These include centrifugation forces, single or double-spin, etc. Even the type of anti-coagulant used when drawing the blood sample can have an affect on the final purity and quality of the PRP.8
One study looking at the effect of ASA on growth factors in PRP found that the type of activation can have a significant affect on the timing, numbers, and levels of different growth factors.9
It’s important to remember that the amount of growth factor release does not always correlate to the changes induced by PRP. Another interesting study looked the affect of PRP on angiogenesis (new blood vessel formation) which was inhibited by ASA. They found that the negative affect of ASA on the PRP could be reversed by certain optimization steps during the preparation (specifically chilling the PRP to 4 °C and supplementing with cryoprecipitate).10
PRP treatments can be a very effective tool for tissue regeneration in many areas of the body. Antiplatelet medications like ASA and Plavix are very important and should never be stopped except under a physician’s advice, as stopping these medications can lead to an increased risk of heart attack or stroke. Despite the fact that ASA and Plavix can interfere with PRP, it does not mean that PRP would have no potential benefit at all. The research is mixed but there are reports of positive effects of using PRP under such circumstances, and PRP itself is considered very safe.
The method of PRP preparation and activation is always important, and even more so when antiplatelet medication is involved.
- 1.Jayaram P, Yeh P, Cianca J. Platelet-rich plasma protocols can potentiate vascular emboli: Contraindications to platelet-rich plasma. J Int Soc Phys Rehabil Med. Published online 2019:104. doi:10.4103/jisprm.jisprm_48_19
- 2.Rao G. Physiology of blood platelet activation. Indian J Physiol Pharmacol. 1993;37(4):263-275. https://www.ncbi.nlm.nih.gov/pubmed/8112802
- 3.Jayaram P, Yeh P, Patel S, et al. Effects of Aspirin on Growth Factor Release From Freshly Isolated Leukocyte-Rich Platelet-Rich Plasma in Healthy Men: A Prospective Fixed-Sequence Controlled Laboratory Study. Am J Sports Med. 2019;47(5):1223-1229. doi:10.1177/0363546519827294
- 4.Ramsook R, Danesh H. Timing of Platelet Rich Plasma Injections During Antithrombotic Therapy. Pain Physician. 2016;19(7):E1055-61. https://www.ncbi.nlm.nih.gov/pubmed/27676677
- 5.Di M, Filardo G, Lo P, Kon E, Marcacci M. Chronic anti-platelet therapy: a contraindication for platelet-rich plasma intra-articular injections? Eur Rev Med Pharmacol Sci. 2014;18(1 Suppl):55-59. https://www.ncbi.nlm.nih.gov/pubmed/24825043
- 6.Frey C, Yeh PC, Jayaram P. Effects of Antiplatelet and Nonsteroidal Anti-inflammatory Medications on Platelet-Rich Plasma: A Systematic Review. Orthopaedic Journal of Sports Medicine. Published online April 1, 2020:232596712091284. doi:10.1177/2325967120912841
- 7.Ludwig HC, Birdwhistell KE, Brainard BM, Franklin SP. Use of a Cyclooxygenase-2 Inhibitor Does Not Inhibit Platelet Activation or Growth Factor Release From Platelet-Rich Plasma. Am J Sports Med. Published online September 27, 2017:3351-3357. doi:10.1177/0363546517730578
- 8.Aizawa H, Kawabata H, Sato A, et al. A Comparative Study of The Effects of Anticoagulants on Pure Platelet-Rich Plasma Quality and Potency. Biomedicines. 2020;8(3). doi:10.3390/biomedicines8030042
- 9.Cavallo C, Roffi A, Grigolo B, et al. Platelet-Rich Plasma: The Choice of Activation Method Affects the Release of Bioactive Molecules. Biomed Res Int. 2016;2016:6591717. doi:10.1155/2016/6591717
- 10.Etulain J, Mena HA, Meiss RP, et al. An optimised protocol for platelet-rich plasma preparation to improve its angiogenic and regenerative properties. Sci Rep. Published online January 24, 2018. doi:10.1038/s41598-018-19419-6