It is hard to believe that seaweed for pain relief has been studied and shown to have some good activity. But natural drugs and treatments are real and have been studied.
What is Pain?
Sensation of pain is vital for survival because it acts as an indicator to tissue-damaging condition in the body. Sensation of pain is initiated in peripheral pain receptors known as nociceptors that are only excited when there is noxious stimulus. Nociceptors are free nerve endings that supply nerves to every tissue of the body except the brain and receptors can be activated by intense thermal, mechanical, or chemical stimuli. Tissue irritation or injury liberates chemicals such as prostaglandins (PGs), kinins, and potassium ion that stimulate nociceptors.
Drugs for Pain Relief
Analgesic drugs are medication that reduce pain. There are several mechanisms of action to provide relief.
- Drugs such as aspirin and ibuprofen block the formation of PGs; thus, nociceptors are not stimulated.
- Local anesthetics such as novocaine block the conduction of nerve impulse along the axons of first-order pain neurons, giving short-term pain relief.
- Morphine and other opiate drugs act by changing the quality of pain perception in the brain.
- Nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the most prescribed medications and have proved to be useful in the management of chronic pain disorders, but prolonged use leads to renal and gastrointestinal side effects. The use of NSAIDs among patients with first-time myocardial infarction was associated with persistent increased coronary risks. There are also the tendency of increased new acute myocardial infraction risk with current use of some NSAIDs, especially parenteral NSAIDs.
Natural Plants and Extracts for Pain Relief
Marine organisms including seaweeds contain biological compounds that have medicinal properties such as analgesic and anti-inflammatory. This research was from Cuba, and Cuba is renowned for lack of western drugs and uses natural products regularly.
So Zakaria and others in an experiment took mice and then gave them acetic acid and measured their writhing. And they confirmed that Pacific Seamoss may possess protective active constituents effective in reducing the sensation of pain in mice.
Read more here in their paper. 
Seaweed for Pain Relief
Customers of Pacific Seamoss experience period pain relief, or pain in exercise. Maybe this is part of the explanation.
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