Spasmolytic herbs have the ability to help reduce smooth muscle spasms. More human studies are needed.
The listings of research below represents a compilation of scientific articles found on the topic, with a very brief overview description of each article/study. This compilation of research articles does not necessarily imply that there are adequate results to demonstrate safe and/or effective human use of any herb listed.
In a meta-review of 12 randomized controled trials and 591 patients, peppermint oil showed spasmolytic activity related to IBS. From: Ford, A. C., Talley, N. J., Spiegel, B. M., Foxx-Orenstein, A. E., Schiller, L., Quigley, E. M., & Moayyedi, P. (2008). Effect of fibre, antispasmodics, and peppermint oil in the treatment of irritable bowel syndrome: systematic review and meta-analysis. Bmj, 337, a2313.
Rosemary was spasmolytic, improved local blood circulation and alleviated pain. From: Sagorchev, P., Lukanov, J., & Beer, A. M. (2010). Investigations into the specific effects of rosemary oil at the receptor level. Phytomedicine, 17(8), 693-697.
H. italicum ssp. italicum was studied in vivo and in vitro and demonstrated an intestinal antispasmodic effect. From: Rigano, D., Formisano, C., Senatore, F., Piacente, S., Pagano, E., Capasso, R., … & Izzo, A. A. (2013). Intestinal antispasmodic effects of Helichrysum italicum (Roth) Don ssp. Italicum and chemical identification of the active ingredients. Journal of ethnopharmacology, 150(3), 901-906.
Researchers studied H. italicum ssp. Italicum flowers in vitro and in vivo and found the ethanolic extract elicited antispasmodic actions in a mouse ileum and inhibited inflammation. From: Senatore, F., Izzo, A. A., Capasso, R., Rigano, D., Borrelli, F., Formisano, C., … & Piacente, S. (2013). Intestinal antispasmodic effects of Helichrysum italicum (Roth) Don ssp. italicum and chemical identification of the active ingredients.
In a scientific study, Pimpinella anisum displayed a smooth muscle relaxant action as used in folk medicine for use as an antispasmodic agent. From: Tirapelli, Carlos R., Claudia R. de Andrade, Adriano O. Cassano, Fernando A. De Souza, Sergio R. Ambrosio, Fernando B. da Costa, and Ana M. de Oliveira. “Antispasmodic and relaxant effects of the hidroalcoholic extract of Pimpinella anisum (Apiaceae) on rat anococcygeus smooth muscle.” Journal of ethnopharmacology 110, no. 1 (2007): 23-29.
Piperine was both gastro-stimulating and antispasmodic in gastrointestinal motility disorders. Link: Mehmood, M. H., & Gilani, A. H. (2010). Pharmacological basis for the medicinal use of black pepper and piperine in gastrointestinal disorders. Journal of medicinal food, 13(5), 1086-1096.
Cardamom oil exerts its analgesic, anti-inflammatory, antispasmodic action in rodents. From: Al-Zuhair, H., El-Sayeh, B., Ameen, H. A., & Al-Shoora, H. (1996). Pharmacological studies of cardamom oil in animals. Pharmacological research, 34(1), 79-82.
Basil oil exerted relaxant effects on intestinal smooth muscle of guinea pigs, and may be considered to treat gastrointestinal disorders. From: Madeira, S. V., Matos, F. J. A., Leal-Cardoso, J. H., & Criddle, D. N. (2002). Relaxant effects of the essential oil of Ocimum gratissimum on isolated ileum of the guinea pig. Journal of Ethnopharmacology, 81(1), 1-4.
There was a relaxant effect of Pimpinella anisum on isolated guinea pig tracheal due to inhibitory effects on muscarinic receptors, demonstrating its potential as a smooth muscle relaxant. From: Boskabady, M. H., & Ramazani-Assari, M. (2001). Relaxant effect of Pimpinella anisum on isolated guinea pig tracheal chains and its possible mechanism (s). Journal of ethnopharmacology, 74(1), 83-88.
In a barium solution mixed with peppermint oil was safe and effective for eliminating colonic spasm during an enema procedure. From: Asao, T., Kuwano, H., Ide, M., Hirayama, I., Nakamura, J. I., Fujita, K. I., & Horiuti, R. (2003). Spasmolytic effect of peppermint oil in barium during double-contrast barium enema compared with Buscopan. Clinical radiology, 58(4), 301-305.
Reasons for peppermint oils spasmolytic effect on the gastrointestinal tract are discussed. From: Grigoleit, H. G., & Grigoleit, P. (2005). Pharmacology and preclinical pharmacokinetics of peppermint oil. Phytomedicine, 12(8), 612-616.
Hyssop essential oil and its constituent isopinocamphone had a muscle relaxing action on the intestine in vitro. From: Lu, M., Battinelli, L., Daniele, C., Melchioni, C., Salvatore, G., & Mazzanti, G. (2002). Muscle relaxing activity of Hyssopus officinalis essential oil on isolated intestinal preparations. Planta medica, 68(03), 213-216.
Hyssop and its linalool constituent showed spasmolytic action on guinea pig ileum. From: Mazzanti, G., Lu, M., & Salvatore, G. (1998). Spasmolytic action of the essential oil from Hyssopus officinalis L. var. decumbens and its major components. Phytotherapy research, 12(S1).
The flavonoid vitexin from Aloysia citriodora contributed to the spasmolytic effect on rat duodenum. From: Ragone, M. I., Sella, M., Conforti, P., Volonté, M. G., & Consolini, A. E. (2007). The spasmolytic effect of Aloysia citriodora, Palau (South American cedrón) is partially due to its vitexin but not isovitexin on rat duodenums. Journal of Ethnopharmacology, 113(2), 258-266
Thymus vulgaris extract was antispasmodic action on guinea pig ileum. From: Babaei, M., Abarghoei, M. E., Ansari, R., Vafaei, A. A., Taherian, A. A., Akhavan, M. M., … & Mousavi, S. (2008). Antispasmodic effect of hydroalcoholic extract of Thymus vulgaris on the guinea-pig ileum. Natural product research, 22(13), 1143-1150.
Thymol has a spasmolytic effect on guinea pig stomach in vitro. From: Beer, A. M., Lukanov, J., & Sagorchev, P. (2007). Effect of Thymol on the spontaneous contractile activity of the smooth muscles. Phytomedicine, 14(1), 65-69.
Thyme extract had an antispasmodic effect on rat ileum and trachea, with thymol being a significant constituent. From: Begrow, F., Engelbertz, J., Feistel, B., Lehnfeld, R., Bauer, K., & Verspohl, E. J. (2010). Impact of thymol in thyme extracts on their antispasmodic action and ciliary clearance. Planta medica, 76(04), 311-318.
Thymus vulgaris had a relaxant effect on guinea pig trachea. From: Boskabady, M. A., Aslani, M. R., & Kiani, S. (2006). Relaxant effect of Thymus vulgaris on guinea‐pig tracheal chains and its possible mechanism (s). Phytotherapy Research, 20(1), 28-33.
Flavonoids from a tea preparation of yarrow had a spasmolytic effect on guinea pig ilea. From: Lemmens-Gruber, R., Marchart, E., Rawnduzi, P., Engel, N., Benedek, B., & Kopp, B. (2006). Investigation of the spasmolytic activity of the flavonoid fraction of Achillea millefolium sl on isolated guinea-pig ilea. Arzneimittelforschung, 56(08), 582-588.
Yarrow extracts had a relaxatory effect on rat ileum. From: Moradi, M., Rafieian-Koupaei, M., Imani-Rastabi, R., Nasiri, J., Shahrani, M., Rabiei, Z., & Alibabaei, Z. (2013). Antispasmodic effects of yarrow (Achillea millefolium L.) extract in the isolated ileum of rat. African Journal of Traditional, Complementary and Alternative Medicines, 10(6), 499-503.
Marrubium vulgare showed antispasmodic activity in vitro. From: Schlemper, V., Ribas, A., Nicolau, M., & Cechinel Filho, V. (1996). Antispasmodic effects of hydroalcoholic extract of Marrubium vulgare on isolated tissues. Phytomedicine, 3(2), 211-216.
Extracts from Viburnum prunifolium showed in vitor relaxant and spasmolytic activity. From: Cometa, M. F., Parisi, L., Palmery, M., Meneguz, A., & Tomassini, L. (2009). In vitro relaxant and spasmolytic effects of constituents from Viburnum prunifolium and HPLC quantification of the bioactive isolated iridoids. Journal of ethnopharmacology, 123(2), 201-207.