S03: Assessing the Need for Therapeutic Innovation in Muscle Cramp Treatments
University of Southern California United States
To gather, analyze, and evaluate scientific and regulatory information that is available to support claims made by products marketed for alleviating muscle cramps; to determine how these products are regulated and if they are meeting the therapeutic needs of patients.
Muscle cramp products were searched on Amazon and depending on type, on PubMed or ClinicalTrials.gov and the Food and Drug Administration (FDA) or
Federal Trade Commission (FTC) warning letter sites to determine the nature of scientific basis for product claims and areas of regulatory compliance.
Previous research identified pickle juice as a popular product for muscle cramps among athletes and examined its scientific evidence and regulatory oversight. Current research expanded upon previous findings to investigate other products used for muscle cramps. Searching “muscle cramps” on Amazon yielded over 3,000 results with a wide variety in product types; when ordered by featured products, the first page of results had 48 items, which were mostly dietary supplements and homeopathic drugs containing various forms of magnesium as a key ingredient. Oral formulations of magnesium included magnesium stearate, magnesium glycinate, and magnesium hydroxide marketed as dietary supplements and various combinations of homeopathic ingredients for Over-the-Counter (OTC) homeopathic products. There were 78 homeopathic drug products that included Cinchona officinalis in its blend among other active ingredients. Although Cinchona officinalis contains quinine, which is associated with serious risks, the homeopathic doses of the product are too low to pose health risks. An FDA warning letter from 2011 on misbranding was found for one such product on Quackwatch.org, but the violations have since been addressed by revisions to the product’s labeling that removed the misleading phrase “with quinine” in the product name. More recently, topical forms of homeopathic remedies for muscle cramps have become widely used. But neither dietary supplement nor homeopathic products undergo FDA review or approval prior to marketing. Most of the regulatory action against these products take place after the products are already on the market and are typically related to poor manufacturing practices or unsubstantiated claims. Review of clinical trials conducted with these products revealed that the field lacks properly conducted trials. Moreover, the available results do not adequately support the claims made by the products on the market.
The lack of scientific studies done on the effectiveness of various muscle cramp treatments reflects the lack of knowledge of the condition and is likely responsible for the abundance of ineffective treatments on the market, as well as the fact that there are many non-drug products like dietary supplements, homeopathic medicine, and food products being offered as remedies. The fact that only a few OTC drug products are available for muscle cramps reveals a therapeutic area that is inadequately addressed and would benefit from novel therapeutics. Although muscle cramps do not often result in serious sequelae, it is a prevalent, diverse, and painful condition affecting physically active individuals and those with confounding factors such as age, pregnancy, and certain medical conditions (e.g. dialysis treatments). Surveys have estimated that 95% of people experience muscle cramps at some point in their lives and that they are often treated by stretching or with OTC analgesics and nonsteroidal anti-inflammatory drugs, which have slow onsets of action and often do not provide quick relief for patients. Considering the ubiquity of muscle cramps, the products currently on the market should be further assessed for the validity of their claims. The findings of this research could inform future researchers regarding gaps in knowledge in this field and the public on the scientific and regulatory basis of these products. Moreover, future regulation and policies for marketing of these products can be revisited to ensure that consumers have access to reliable treatments for this common condition.