Is Tylenol Good For Period Cramps?
Tylenol is not as effective as some of the NSAIDs (ibuprofen, naproxen) for period cramps. Studies done on women who experience period cramps tends to benefit more with NSAIDs than acetaminophen such as Tylenol. The exact reason for this is unknown, but studies done on women with period cramps shows that pain relief with NSAIDs are slightly more effective than Tylenol for period cramps.
The reason might be that acetaminophen has a weak inhibition of PG’s in the peripheral tissue and also it does not reduce the inflammation in the uterus. It mainly has an analgesic effect on the uterus which might not be enough to relieve severe pain.
Women with mild to moderate period cramps usually benefit with acetaminophen, but with severe cramps are not relieved with acetaminophen.1
How Does Tylenol Reduce Pain?
Tylenol also known as paracetamol, the generic name is acetaminophen. Paracetamol is a simple analgesic and an antipyretic. It’s more than 100 years after finding acetaminophen, but still the exact mechanism of action of acetaminophen is unknown.2 There are several theories on how acetaminophen relieves period cramps; it has shown that acetaminophen has effects on prostaglandin production, nitric oxide, opioid, serotonergic, and cannabinoid pathways. It is believed that interaction of all those pathways bring about the action of acetaminophen.3 We will be only talking about the prostaglandin inhibition theory in this article.
Some researchers say that Tylenol inhibits prostaglandin (PG) production but in a different way than the NSAID’s. Acetaminophen does not induce an anti-inflammatory reaction; therefore, it is believed that the PG inhibition is not achieved through inhibiting COX-1 and COX-2 pathway as in NSAID’s. Arachidonic acid metabolizes into prostaglandin H2 synthetase (PGHS) which has two active sites the cyclooxygenase (COX) site and peroxidase site. The NSAIDs act on the COX pathway to inhibit PG production whereas, acetaminophen inhibit the peroxidase site which inhibit the PG production. It acts in a peroxidase dependent COX inhibition to stop PG production.4
When the peroxidase concentration is high acetaminophen weakly inhibit the PG production. In the brain the peroxidase concentration is low but in the peripheral tissues the peroxidase concentration is high, therefore inhibition of PG is weak in the peripheral tissues.
There is another suggested mechanism that is acetaminophen inhibits a variant of COX-1 named COX-3. This can explain why acetaminophen lacks anti-inflammatory and anti-platelet effect, but has strong analgesic and anti-pyretic effect. But this theory is not proven yet.5
What Are Period Cramps?
Period cramps or dysmenorrhea is one of the common reasons for a woman to visit a doctor. Period cramps is painful cramps associated with menstruation. Usually in a woman every month menstruation occurs when the egg is not fertilized due to hormonal changes. The inner lining tissue of the uterus and blood pass as menses through the vagina. The exact cause for period cramps is not known but there are several theories.6
Prostaglandin is produced in the uterus, which contracts the uterine muscle to expel the menstrual blood. The severity of the pain directly proportional to the amount of prostaglandin that is produced. If more prostaglandin is produced the uterine muscles contract vigorously, giving severe pain.7
Leukotrienes produced tends to heighten the sensitivity to pain in the pain fibers of the uterus.8
Vasopressin also increase uterine muscle contractions, reduce blood flow and induce pain. It also has some effect on the production and release of prostaglandin.
Tylenol also known as paracetamol, the generic name is acetaminophen. The exact mechanism of action of acetaminophen is unknown. It has a strong analgesic and anti-pyretic effect but lacks anti-inflammatory properties. Tylenol is not as effective as some of the NSAIDs (Ibuprofen, Naproxen) for period cramps. Studies done on women who experience period cramps tends to benefit more with NSAIDs than acetaminophen. The exact reason for this is unknown, might be that acetaminophen has a weak inhibition of PG’s in the peripheral tissue and also it does not reduce the inflammation in the uterus. It mainly has an analgesic effect on the uterus which might not be enough to relieve severe period cramps.