I've Taken My Painkillers, So Why Do I Still have Period Cramps?

Let’s say you have period cramps. You've taken medicine for it. And you're still in real pain, wondering why it doesn't seem to be working the way it's supposed to. Or whether there might be something wrong with you. 

Unfortunately, this is far more common than it seems. Around 71% of people who menstruate deal with period cramps [1]. And research found that around half of women continue to have pain even after taking medication properly [2]. So many women experience serious pain that affects their daily functioning, with little explanation of why their painkillers aren’t cutting it.

There can be multiple reasons why painkillers are not doing their job. Let’s go through them together!

A quick disclaimer before we do: I'm not a medical doctor, I'm a medical and health psychologist. This isn't medical advice, and it doesn't replace an actual conversation with your own doctor. What follows is based on scientific literature. 

Quickly, what's even causing the pain

Most period pain comes from chemicals called “prostaglandins”, inflammatory compounds your uterus releases to help it contract and shed its lining [3]. Prostaglandins are necessary for the uterus to shed its lining. But if your body produces an excessive amount (more than your body needs), the uterus cramps harder than necessary, cutting off blood flow to the area and irritating the pain nerves [4]. For those who want to understand why there would be an excessive amount of prostaglandins - it’s caused by multiple factors, including progesterone withdrawal, diet and genetics [5 ].

To put it very simply: lots of prostaglandins = uterus cramping and pain

A visualisation: Clench your fist as hard as you can, notice the blood draining out and the ache starting, that's roughly what's happening with your uterus when there are too many prostaglandins.

Possibility one: you're reaching for the wrong thing

What are you taking when experiencing period cramps? Paracetamol (brandnames: panadol, tylenol, mexalen) doesn't meaningfully block prostaglandin production, which is the actual job that needs to be done here [6]. Paracetamol is not the most effective medication to be taking for period pain specifically.

Instead, Non-Steroidal Anti Inflammatory Drugs - NSAIDs (ibuprofen, naproxen, brandnames: advil, motrin, nurofen, aleve etc.) have been found to be more effective than paracetamol [7]. More on this next.

Possibility two: you're taking it at the wrong time

A really easy adjustment that could reduce your period pain is the timing of taking medication. NSAIDs work by blocking the enzyme that produces prostaglandins (the stuff that makes the pain) in the first place. They can only block prostaglandin that has not been made yet [8]. 

• If you take it early - at the first sign of your period (such as spotting, or a dull ache), or even the day before if you are able to predict it, you could prevent some of the prostaglandin production and prevent pain from starting at all [9]. 

• If you take it when you are already experiencing strong pain, prostaglandins have already been produced and having negative cramping effects on the uterus. The medication then cannot stop or prevent pain as effectively. 

And keep taking it on a schedule, not just once [10]. NSAIDs wear off after a few hours (ibuprofen after roughly 4 to 6, naproxen a bit longer), and prostaglandins will start being released again. One early dose only covers the first stretch. Mayo Clinic's recommends to keep dosing on schedule for 2-3 days, not just once it starts hurting [1]. If you take medication and wait too many hours to take the next dose, you give your body the chance to produce more prostaglandins again.

Make sure to talk to your doctor or pharmacist about this, since using ibuprofen does have risks such as stomach ulcers, kidney issues, asthma, and should not be taken during pregnancy.  

What research says can help reduce pain: 

This is by no means an extensive or complete list, but it gives some good starting points for how to manage your period pain without medicine.

1. Heat: Heat applied directly to the lower abdomen, meaningfully reduces pain in a way that's held up well in research, in some trials about as well as NSAIDs [12]. Go back to the fist visualisation from earlier: heat doesn't just restore the blood flow that clenching cut off, it also relaxes the muscle itself, getting your uterus out of the tensed state. It's the physical equivalent of slowly unclenching your fist, instead of it staying squeezed. 

2. Omega-3: Taking omega-3 supplements has been found to reduce period pain [13]. The studies have found a 22-66% reduction in pain severity - the variation likely depends on the dose, and how they tested outcomes. Specifically, omega-3 is expected to reduce prostaglandin production [14]. Omega-3s should be taken throughout the whole cycle, and are a long term-solution, rather than an acute solution. Since there is not that much research, specific guidelines on how much omega-3 to take for period pain specifically are not developed - the studies cited typically used around 1000mg of combined EPA and DHA. Again, ask your doctor what a good dose is!

3. Movement: Slow, low-intensity movement (such as yoga, walking, stretching) practiced consistently across your cycle rather than only during menstruation, has also been shown to help period pain over time [15]. It is of course important to listen to your body, and not force yourself to do high intensity exercise while experiencing severe pain. 

4. Redlight therapy: This is the use of a special light that stimulates biological responses. Studies have shown a reduction in period pain after using red light therapy [16]. It is expected to work by reducing prostaglandin production, reducing inflammation, and reducing muscle contractions. Red light therapy is especially expected to be more effective when using it for multiple weeks (benefits were stronger at 12 weeks, ran at 4 weeks or 8 weeks). There are a lot of products online - to me a belt-like product seems the most practical. 

   A recent study has proposed the following guidelines based on previous research: the wavelength should be red light (610-630nm), it should be applied for 20 minutes, daily for 5 consecutive days before menstruation, as well as during menstruation [17]. 

5. Diet: Diet is an incredibly complex topic (in which I am not specialised), and everyone has different perspectives on what a “healthy diet” really is. As a general principle, it is clear that having an anti-inflammatory diet, and avoiding heavily processed foods is related to reduced period pain [18]. 

6. Vitamin D: Vitamin D supplementation has been shown to reduce period pain [19]. Vitamin D deficiency is associated with higher levels of prostaglandins in the endometrium [20]. The doses taken in the scientific articles are very high - higher than the general guidelines (~600IU) . Ask your doctor what doses of vitamin D are safe for you to use. 
   

Possibility three: it's genuinely more than prostaglandins can explain

If you've optimised your medication intake - the optimal medication, timing, and schedule, and you are still in pain, you are not alone in that either [21]. This is really common. Multiple studies have found that even after taking NSAIDs properly, around half of women continue to experience pain. NSAIDs clearly help, but "helps" isn't the same as "getting rid of the majority of pain". I find it upsetting (but not surprising) to read how many people experience period pain that is not adequately stopped by recommended medications.

Period pain is mainly caused by excessive prostaglandins. But there are also other chemicals such as leukotrienes and vasopressin, which contribute to period pain [22]. However drugs that target these chemicals have had mixed results during small trials, which is why they are not being recommended. 

Possibility four: it might not be ordinary period pain at all

If none of the above fully explains it, especially if the pain is severe, unpredictable, or doesn't stay contained to your period, it's worth asking a doctor whether something like endometriosis or adenomyosis could be involved. In these conditions, there is a lot more happening than “just” prostaglandins. Endometriosis can involve broader symptoms such as (but definitely not limited to): 

• Pain during sex

• Bowel or bladder pain during your period

• Cramps that continue throughout your cycle, not just around your period.

You can read more about endometriosis here. 

If you think you might have endometriosis, make sure to be proactive and go to a doctor (or multiple if needed), and get your symptoms checked. For example, you could say: “I've been taking [drug] correctly, on a schedule of [X] pills/mg every [X] hours and I am still getting an [X]/10 pain.”. Persistent pain that doesn't respond to properly-used pain killers is a legitimate reason to keep asking questions. 

Pain is not just physical, it is also psychological. Your mood, expectations and where you focus your attention towards, can really change how much pain you experience. Pain should therefore be managed on a medical but also a psychological level. For example, noticing you are bracing for pain can itself make the pain feel worse and bringing yourself back to a more relaxed state can help. Read more about the psychology of pain here.

Another reason why period or endometriosis pain can be hard to treat with standard painkillers is: central sensitization. This is when the nervous system itself becomes more reactive over time, and pain can persist even once the original trigger is addressed. I won’t go into depth with that now, since it deserves its own space and nuanced explanations.

Where that leaves you

Take NSAIDs (if your doctor agrees), before experiencing strong pain, at a regular schedule. Try using: heat, omega-3s, movement, red-light therapy, adjusting your diet, and vitamin D as complementary pain management methods. And if your pain still persists, look into whether you might have endometriosis or adenomyosis.

It is a shame that this information is not common knowledge or taught in schools. Something that affects the majority of menstruating people still doesn't come with clear information. 

References:

1. Guilherme Tavares de Arruda et al., “Worldwide Prevalence of Dysmenorrhea: A Systematic Review and Meta-Analysis across 70 Countries,” Pain 167, no. 1 (2026): 41–55, https://doi.org/10.1097/j.pain.0000000000003768.

2. Folabomi A. Oladosu et al., “Nonsteroidal Antiinflammatory Drug Resistance in Dysmenorrhea: Epidemiology, Causes, and Treatment,” American Journal of Obstetrics and Gynecology 218, no. 4 (2018): 390–400, https://doi.org/10.1016/j.ajog.2017.08.108.

3. ladosu et al., “Nonsteroidal Antiinflammatory Drug Resistance in Dysmenorrhea”;

   Inês Guimarães and Ana Margarida Póvoa, “Primary Dysmenorrhea: Assessment and Treatment,” Revista Brasileira de Ginecologia e Obstetrícia (Brazil) 42, no. 8 (2020): 501–7, https://doi.org/10.1055/s-0040-1712131.

4. Zofia Barcikowska et al., “Inflammatory Markers in Dysmenorrhea and Therapeutic Options,” International Journal of Environmental Research and Public Health (Switzerland) 17, no. 4 (2020): 1191--, https://doi.org/10.3390/ijerph17041191;

   V. Lundström and K. Gréen, “Endogenous Levels of Prostaglandin F2alpha and Its Main Metabolites in Plasma and Endometrium of Normal and Dysmenorrheic Women,” American Journal of Obstetrics and Gynecology 130, no. 6 (1978): 640–46, https://doi.org/10.1016/0002-9378(78)90320-4.

5. Oladosu et al., “Nonsteroidal Antiinflammatory Drug Resistance in Dysmenorrhea.”

6. Jane Marjoribanks et al., Nonsteroidal Anti‐inflammatory Drugs for Dysmenorrhoea - Marjoribanks, J - 2015 | Cochrane Library, n.d., accessed September 17, 2026, https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD001751.pub3/full;

   Garry G. Graham and Kieran F. Scott, “Mechanism of Action of Paracetamol,” American Journal of Therapeutics 12, no. 1 (2005): 46–55, https://doi.org/10.1097/00045391-200501000-00008.

7. Comparison between Ibuprofen and Paracetamol in Primary Dysmenorrhea – Hjog.Org, January 29, 2022, https://hjog.org/?p=2399.C

8. David J. Bjorkman, “The Effect of Aspirin and Nonsteroidal Anti-Inflammatory Drugs on Prostaglandins,” The American Journal of Medicine 105, nos. 1, Supplement 2 (1998): 8S-12S, https://doi.org/10.1016/S0002-9343(98)00069-2.

9.  Rupam Majee, “Reviewed Literature on Use of Ibuprofen and Other NSAIDs in the Management of Menstrual Cramps,” International Journal of Pharmaceutical Sciences 04, no. 09 (2026): 1837–50, World, https://doi.org/10.5281/zenodo.22767867.maj

10. Margaret Burnett, “Guideline No. 345: Primary Dysmenorrhea,” Journal of Obstetrics and Gynaecology Canada: JOGC = Journal d’obstetrique et Gynecologie Du Canada: JOGC 47, no. 5 (2025): 102840, https://doi.org/10.1016/j.jogc.2025.102840.

11. “Menstrual Cramps-Menstrual Cramps - Diagnosis & Treatment,” Mayo Clinic, accessed September 18, 2026, https://www.mayoclinic.org/diseases-conditions/menstrual-cramps/diagnosis-treatment/drc-20374944.

12. Dongni Yuan et al., “Heat Therapy for Primary Dysmenorrhea: A Systematic Review and Meta-Analysis,” Frontiers in Medicine 12 (n.d.): 1730505, https://doi.org/10.3389/fmed.2025.1730505.

13. Rhiannon M. J. Snipe et al., “Omega-3 Long Chain Polyunsaturated Fatty Acids as a Potential Treatment for Reducing Dysmenorrhoea Pain: Systematic Literature Review and Meta-Analysis,” Nutrition & Dietetics: The Journal of the Dietitians Association of Australia 81, no. 1 (2024): 94–106, https://doi.org/10.1111/1747-0080.12835.

14. Ashley S. Roman et al., “Omega-3 Fatty Acids and Decidual Cell Prostaglandin Production in Response to the Inflammatory Cytokine IL-1β,” American Journal of Obstetrics & Gynecology 195, no. 6 (2006): 1693–99, https://doi.org/10.1016/j.ajog.2006.04.009.

15.  Paloma Carroquino-Garcia et al., “Therapeutic Exercise in the Treatment of Primary Dysmenorrhea: A Systematic Review and Meta-Analysis,” Physical Therapy (United States) 99, no. 10 (2019): 1371–80, https://doi.org/10.1093/ptj/pzz101.

16. Lin Ang et al., “Effectiveness and Safety of Light Therapy for Treating Primary Dysmenorrhea: A Systematic Review and Meta-Analysis of Randomized Controlled Trials,” Complementary Therapies in Medicine 93 (October 2025): 103232, https://doi.org/10.1016/j.ctim.2025.103232.

17.  Elizabeth Pelevin et al., “Mechanistic Insights Into Photobiomodulation for Primary Dysmenorrhea: A Narrative Review,” Curēus (Palo Alto, CA) (United States) 18, no. 3 (2026): e104721-, https://doi.org/10.7759/cureus.104721.

18. Emily Sergio et al., “Investigating the Association between Diet and Primary Dysmenorrhea: A Systematic Review,” F&S Reviews 7, no. 2 (2026), https://doi.org/10.1016/j.xfnr.2026.100112.

19. Fatemeh Alsadat Rahnemaei et al., “Vitamin D Supplementation for Primary Dysmenorrhea: A Double-Blind, Randomized, Placebo-Controlled Trial,” Obstetrics & Gynecology Science 64, no. 4 (2021): 353–63, https://doi.org/10.5468/ogs.20316;

    Iris Wenyu Zhou et al., “Vitamin D for Primary Dysmenorrhea and Endometriosis-Related Pain – A Systematic Review of Registered RCTs,” PLOS ONE 20, no. 4 (2025): e0321393, https://doi.org/10.1371/journal.pone.0321393.

20. Chandrasekhar Thota et al., “Vitamin D Regulates Contractile Profile in Human Uterine Myometrial Cells via NF-κB Pathway,” American Journal of Obstetrics and Gynecology (United States) 210, no. 4 (2014): 347.e1-347.e10, https://doi.org/10.1016/j.ajog.2013.11.027.

21. Marjoribanks et al., Nonsteroidal Anti‐inflammatory Drugs for Dysmenorrhoea - Marjoribanks, J - 2015 | Cochrane Library.

22. Barcikowska et al., “Inflammatory Markers in Dysmenorrhea and Therapeutic Options.”