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Flex (SC)


* Spasms and cramps:

§ Skeletal muscles in the extremities

§ Smooth muscles in the internal organs

* Muscle tightness and stiffness due to repetitive movements

* External injuries with muscle sprain and strain



* Muscle-relaxant effect to treat muscle spasms and cramps

* Anti-inflammatory function to reduce inflammation and swelling

* Analgesic effect to relieve pain



* Tonifies Liver yin and Liver blood

* Relieves spasms and cramps

* Tonifies the blood

* Warms the meridians and unblocks stagnation

* Invigorates blood circulation



Take 3 to 4 capsules every four to six hours as needed for muscle spasms and cramps. The dosage may be increased up to 5 to 6 capsules every two to four hours if necessary. For maximum effectiveness, take Flex (SC) on an empty stomach with a tall glass of warm water.



Bai Shao (Radix Paeoniae Alba)

Dang Gui Wei (Extremitas Radix Angelicae Sinensis)

Hua Jiao (Pericarpium Zanthoxyli)

Zhi Gan Cao (Radix et Rhizoma Glycyrrhizae Praeparata cum Melle)



Muscle spasms and cramps are involuntary and sometimes painful contractions of the muscles. Spasms and cramps affect many muscle groups, including but not limited to leg, calf, thigh, hands, arms, abdomen, and intestines. Common causes of muscle spasms and cramps include overuse or injury of a muscle, dehydration, electrolyte imbalance, excessive consumption of alcohol, certain disease state (hypothyroidism, kidney failure), and use of drugs (diuretics). Stretching and adequate intake of fluids with sufficient amount of potassium are the best preventative measures for spasms and cramps. If necessary, herbs that relax the muscles can also be used.



Flex (SC) is formulated to relieve muscle spasms and cramps. According to traditional Chinese medicine, the etiology of muscle spasms and cramps is Liver yin and Liver blood deficiencies. Effective treatment, therefore, must focus on nourishing Liver yin and Liver blood deficiencies, activating qi and blood circulation, and removing stagnation.

        Bai Shao (Radix Paeoniae Alba) tonifies Liver yin and Liver blood to relieve spasms and cramps. Paeoniflorin, the active constituent in Bai Shao (Radix Paeoniae Alba), has strong analgesic, antispasmodic and anti-inflammatory effects. Together with the harmonizing function of Zhi Gan Cao (Radix et Rhizoma Glycyrrhizae Praeparata cum Melle), they nourish and relax the tendons and smooth muscles. Hua Jiao (Pericarpium Zanthoxyli) and Dang Gui Wei (Extremitas Radix Angelicae Sinensis) are used to warm peripheral channels and collaterals and invigorate qi and blood circulation.



* This formula should not be taken long-term in patients who have hypertension, as prolonged use of Zhi Gan Cao (Radix et Rhizoma Glycyrrhizae Praeparata cum Melle) may be associated with water retention.

* This herbal formula contains herbs that invigorate blood circulation, such as Dang Gui Wei (Extremitas Radix Angelicae Sinensis). Therefore, patients who are on anticoagulant or antiplatelet therapies, such as Coumadin (warfarin), should use this formula with caution, or not at all, as there may be a higher risk of bleeding and bruising.[1],[2],[3]



* To enhance the analgesic effect, add Herbal ANG.

* For neck and shoulder pain, combine with Neck & Shoulder (AC) or Neck & Shoulder (CR).

* For lower back pain, combine with Back Support (AC) or Back Support (CR).

* For pain in the arm (shoulder, elbow and wrist), add Arm Support.

* For knee pain, combine with Knee & Ankle (AC) or Knee & Ankle (CR).

* For chronic musculoskeletal disorder with damaged soft tissues (muscles, tendons, ligaments, and cartilage), add Flex (MLT).

* For arthritis with inflammation, swelling, redness and pain, combine with Flex (Heat).

* For arthritic pain that worsens during cold and rainy weather, combine with Flex (CD).

* For bone fractures, injuries, and bruises, combine with Flex (TMX).

* To improve blood circulation to the extremities, combine with Flex (NP).

* For bone spurs, add Flex (SPR).

* For osteoporosis, add Osteo 8.

* For severe blood stagnation, add Circulation (SJ).

* For dryness and thirst, add Nourish (Fluids).



Traditional Points:

* Shousanli (LI 10), Waiguan (TH 5), Zusanli (ST 36)

* Zhigou (TH 6), Zusanli (ST 36), Zhongwan (CV 12), Neiguan (PC 6), Guanyuan (CV 4), Taichong (LR 3), Shenque (CV 8)


Classic Master Tung's Points:

* Needle contralateral to the pain. If the pain is in the center, needle bilaterally or the side with the more ah shi points. If the pain is bilateral, needle bilaterally.

* Linggu (T 22.05), Wanshunyi (T 22.08), Wanshuner (T 22.09), Zhongguan (T 22.25)*, Zhengjin (T 77.01), Zhengzong (T 77.02), Zhengshi (T 77.03), Tianhuang (T 77.17), Dihuang (T 77.19), Renhuang (T 77.21)

* Medial calf pain: Ganlingsan (T 33.18)*, Xinmen (T 33.12), Changmen (T 33.10), Ganmen (T 33.11)


Master Tung’s Points by Dr. Chuan-Min Wang:

* Spasms, cramps: Zhongjiuli (T 88.25), Qili (T 88.51)*, Sanchasan (T 22.17)*


Balance Method by Dr. Richard Tan:

* Use Dr. Tan’s Balance Method accordingly as determined by where the pain is (use mirror or image system).


Auricular Medicine by Dr. Li-Chun Huang:

* Spasm: Sympathetic, Nervous Subcortex, Shenmen, corresponding points (to the area affected). Bleed Ear Apex.

* Calf cramps: Calf, Popliteal Fossa, Lesser Occipital Nerve, Liver, Spleen, Coronary Vascular Subcortex



* Drink large amounts of water throughout the day (steam-distilled) to hydrate the muscles and flush out toxins residing in the muscles.

* To prevent muscle cramps and spasms, eat plenty of fruits and vegetables, especially those high in potassium, such as bananas and oranges.

* Avoid foods that increase the acidity of the body, such as red meat, baked goods, sweet foods, and processed foods.

* Increase the intake of foods rich in alkaline minerals, such as fresh raw vegetables, alfalfa sprouts, and seaweed.



* Cigarette smoking and alcohol intake should be avoided as they dry out yin and may cause more cramping.

* Warm baths relax the tense muscles and relieve spasms and cramps.

* Avoid tight shoes and clothing, which impair normal circulation of blood to peripheral parts of the body.

* Stretch for at least 30 minutes daily, especially before exercising.



* E.B., a 79-year-old female, presented with stiffness of the middle and ring fingers on the right hand. She was neither able to close her hand and make a fist, nor was she also able to extend her fingers. The range of motion was greatly reduced, and she was unable to sculpt. The patient refused to see a medical doctor. The previous carpal tunnel syndrome (CTS) surgery in 1983 left a small scar in the palm of her hand. The tendons of the palm were very tight, ropy in quality, enlarged and swollen. The palms were red, the skin was dry and the nails were brittle. She also complained of dry mouth and throat at night. The Western diagnoses were contraction of the palmar fascia and Dupuytren’s Contracture. The TCM diagnoses were bi zheng (painful obstruction syndrome), Liver and Kidney yin deficiencies, and blood stagnation. Acupuncture, micro-current, massage, and Flex (SC) were all part of the treatment regime that helped her gain 90% range of motion within one week. She was almost able to close her hands and make a fist. The palm was less red and the swelling decreased. The patient was thrilled. Submitted by M.H., West Palm Beach, Florida.

* A 44-year-old female presented with upper back spasm. The patient stated: “It feels like creepy crawlers.” In addition to her upper back dysfunction, floaters were also present with bright lights disturbing her eyes. The practitioner diagnosed her condition as Liver qi stagnation with Liver yin deficiency. After taking Flex (SC), the patient was calmer, more relaxed, and had fewer moods swings. Consequently, she was not as irritable and had less muscle spasms in her mid back. She also slept much better. Submitted by D.M., Raton, New Mexico.

* L.P., a 77-year-old female, presented with severe pain in the left wrist and right rib cage after a fall. She had numbness of the wrist and palm where she landed on the cement. The patient showed bruises on the right eye. The right wrist was painful to light movement and palpation. There were tender points on the right subclavicular area. There were no visible contusions on the right rib cage. The diagnoses were qi and blood stagnation with soft tissue damage. Flex (TMX), Neck & Shoulder (AC) and Flex (SC) were prescribed at 2 capsules of each formula three times daily. The patient reported daily lowering of pain levels. Numbness was reduced to a light tingling after two days. She reported continuous and steady improvement each day. She was instructed to reduce the dosage to 2 capsules of each formula twice a day when the pain subsided. After the swelling was reduced, the patient was referred to a chiropractor for cervical and occipital adjustments. Submitted by M.H., West Palm Beach, Florida.

* D.D., a 41-year-old nurse, presented with a work-related injury. She had severe back pain that was the result of a fall from lifting a patient. She said she heard a popping sound in her back when she fell. MRI confirmed her diagnosis of lumbar herniated disc. She was nine weeks post-injury and had scheduled for steroid epidurals. She refused injections and came to our clinic for ‘safe and non-invasive care.’ Her blood pressure was 140/80 mmHg and the heart rate was 80 beats per minute. The TCM diagnoses include qi and blood stagnation and soft tissue damage. Back Support (AC), Flex (SC) and Flex (TMX) were prescribed at 3 capsules each three times a day. After the herbs, the patient was able to reduce Vicodin (APAP/hydrocodone) use from 2 to 0.5 tablets per day, and none at all on some days. She had increased blood pressure from stress over the injury, which was up to 170/110 mmHg. After the herbs and massage, the blood pressure came down to normal and is staying down. She had received no additional physical therapy. She did remarkably well in a short period of time. Submitted by M.H., West Palm Beach, Florida.



Flex (SC) is formulated based on a classic Chinese herbal formula, Shao Yao Gan Cao Tang (Peony and Licorice Decoction), which has been used for approximately two thousands years to treat spasms and cramps of skeletal and intestinal muscles. Modern research has confirmed the ingredients of Flex (SC) to have excellent muscle-relaxant, analgesic and anti-inflammatory effects.

        The combination of Bai Shao (Radix Paeoniae Alba) and Gan Cao (Radix et Rhizoma Glycyrrhizae) has an excellent muscle-relaxant effect to relax both smooth and skeletal muscles.[4],[5] Clinically, these two herbs have been used successfully to treat conditions such as leg cramps in the calf,[6] muscle cramps in hemodialysis,[7] restless leg syndrome,[8] intestinal spasms,[9] facial spasms and twitching,[10] and menstrual cramps and pain.[11]

        Bai Shao (Radix Paeoniae Alba) and Gan Cao (Radix et Rhizoma Glycyrrhizae) also have a marked analgesic effect to relieve pain. The effectiveness is increased significantly when combined with acupuncture.[12] Clinically, these two herbs have been used successfully to treat conditions such as pain,[13] neuralgia,[14] trigeminal neuralgia,[15],[16] neck pain, [17] acute back pain,[18] heel pain,[19] pain in the lower back and legs,[20] sciatica,[21] gastric and abdominal pain,[22] and dysmenorrhea.[23]

        Lastly, Bai Shao (Radix Paeoniae Alba) and Gan Cao (Radix et Rhizoma Glycyrrhizae) are commonly used to treat inflammatory disorders, as they have a synergistic effect when used together. Bai Shao (Radix Paeoniae Alba) has an excellent anti-inflammatory effect to reduce swelling and inflammation by modulating the pro-inflammatory mediators production from macrophage-like synoviocytes.[24] Gan Cao (Radix et Rhizoma Glycyrrhizae) has marked anti-inflammatory function by enhancing the effect of glucocorticoid through increased production and secretion, as well as decreased metabolism by the liver, or increased plasma concentration caused by decreased protein binding.[25] Clinical applications include pain, inflammation, edema, arthritis, spasms, cramps and others.[26],[27]

        Flex (SC) incorporates Dang Gui (Radix Angelicae Sinensis) and Hua Jiao (Pericarpium Zanthoxyli) to enhance the analgesic and anti-inflammatory effects. Hua Jiao (Pericarpium Zanthoxyli) exerts its anti-inflammatory effect by inhibiting the pro-inflammatory cytokines and suppressing the vascular inflammatory process.[28] Dang Gui (Radix Angelicae Sinensis) reduces inflammation through the inhibition of pro-inflammatory mediators, including nitric oxide and prostaglandin E2 in peritoneal macrophages.[29],[30] In comparison with acetylsalicylic acid, the anti-inflammatory effect of Dang Gui (Radix Angelicae Sinensis) is approximately 1.1 times stronger, and its analgesic effect is approximately 1.7 times stronger.[31] According to clinical studies, Dang Gui (Radix Angelicae Sinensis) has been used successfully to treat menstrual pain in 112 patients,[32] migraine headache in 35 patients,[33] different types of headache in 36 patients,[34] and general complaint of pain in 105 patients.[35]

        In summary, Flex (SC) is an excellent formula to treat spasms and cramps affecting both skeletal and smooth muscles.



Spasms and cramps are common musculoskeletal complaints that can be treated effectively with both drug and herbal therapies. In Western medicine, muscle relaxants such as Soma (carisoprodol) and Flexeril (cyclobenzaprine) are generally prescribed for spasms and cramps. These drugs are only mild to moderate in potency. However, they are also relatively safe, with relatively mild side effects such as blurred or double vision, dizziness, lightheadedness, and drowsiness.

        Herbs that nourish yin and replenish fluids are most effective to relax the muscles. These herbs are also of mild to moderate potency, and are associated with few or no side effects.

        Drugs and herbs have a comparable effect to treat spasms and cramps, and both are associated with few side effects. In addition to drug or herbal therapies, one can incorporate non-medicine modalities to enhance overall effectiveness, such as drinking water, stretching affected muscles, and taking potassium, magnesium and calcium supplements.


[1] Chan K, Lo AC, Yeung JH, Woo KS. Journal of Pharmacy and Pharmacology 1995 May;47(5):402-6.

[2] Pharmacotherapy 1999 July;19(7):870-876.

[3] European Journal of Drug Metabolism and Pharmacokinetics 1995; 20(1):55-60.

[4] Guo Wai Yi Xue (Foreign Medicine) 1984;6(1):58.

[5] He Nan Zhong Yi (Henan Chinese Medicine) 1986;(6):15.

[6] Zhong Yi Za Zhi (Journal of Chinese Medicine) 1985;6:450.

[7] Inoshita F, Ogura Y, Suzuki Y, Hara S, Yamada A, Tanaka N, Yamashita A, Marumo F. Effect of orally administered shao-yao-gan-cao-tang (Shakuyaku-kanzo-to) on muscle cramps in maintenance hemodialysis patients: a preliminary study. American Journal of Chinese Medicine 2003;31(3):445-53.

[8] He Bei Zhong Yi (Hebei Chinese Medicine) 1984;3:29.

[9] Zhong Yi Za Zhi (Journal of Chinese Medicine), 1985; 6:50.

[10] Zhong Xi Yi Jie He Za Zhi (Journal of Integrated Chinese and Western Medicine), 1991; (1):43.

[11] Bei Jing Zhong Yi (Beijing Chinese Medicine) 1983;(1):33.

[12] Guo Wai Yi Xue (Foreign Medicine) 1984;6(1):58.

[13] Shang Hai Zhong Yi Yao Za Zhi (Shanghai Journal of Chinese Medicine and Herbology), 1983; 4:14.

[14] Zhong Yi Ming Fang Lin Chuang Xin Yong (Contemporary Clinical Applications of Classic Chinese Formulas) 2001;313.

[15] Jiang Xi Yi Yao (Jiangxi Medicine and Herbology) 1965;5(7):909.

[16] Zhong Yi Za Zhi (Journal of Chinese Medicine), 1983; 11:9.

[17] Jiang Su Zhong Yi (Jiangsu Chinese Medicine), 1990; (10):29.

[18] Zhe Jiang Zhong Yi Za Zhi (Zhejiang Journal of Chinese Medicine) 1995;(11):524.

[19] Si Chuan Zhong Yi (Sichuan Chinese Medicine) 1996;11:38.

[20] Yun Nan Zhong Yi (Yunnan Journal of Traditional Chinese Medicine), 1990; 4:15.

[21] Fu Jian Zhong Yi Yao (Fujian Chinese Medicine and Herbology), 1994; (1):7.

[22] Fu Jian Zhong Yi Yao (Fujian Chinese Medicine and Herbology) 1961;9(4):44.

[23] Tanaka T. A novel anti-dysmenorrhea therapy with cyclic administration of two Japanese herbal medicines. Clinical & Experimental Obstetrics & Gynecology 2003;30(2-3):95-8.

[24] Zheng YQ, Wei W. Total glucosides of paeony suppresses adjuvant arthritis in rats and intervenes cytokine-signaling between different types of synoviocytes. Int Immunopharmacol. 2005 Sep;5(10):1560-73.

[25] Zhong Yao Zhi (Chinese Herbology Journal), 1993; 358.

[26] Zhe Jiang Zhong Yi Za Zhi (Zhejiang Journal of Chinese Medicine), 1980; 2:60.

[27] Zhong Hua Nei Ke Za Zhi (Chinese Journal of Internal Medicine), 1960; 4:354.

[28] Cao LH, Lee YJ, Kang DG, Kim JS, Lee HS. Effect of Zanthoxylum schinifolium on TNF-alpha-induced vascular inflammation in human umbilical vein endothelial cells. Professional Graduate School of Oriental Medicine, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea. Vascul Pharmacol. 2009 May-Jun;50(5-6):200-7.

[29] Xin Yi Yao Xue Za Zhi (New Journal of Medicine and Herbology), 1975; (6):34.

[30] Chao WW, Kuo YH, Li WC, Lin BF. The production of nitric oxide and prostaglandin E2 in peritoneal macrophages is inhibited by Andrographis paniculata, Angelica sinensis and Morus alba ethyl acetate fractions. Department of Biochemical Science and Technology, Institute of Microbiology and Biochemistry, National Taiwan University, Taipei 106, Taiwan, ROC. J Ethnopharmacol. 2009 Feb 25;122(1):68-75.

[31] Yao Xue Za Zhi (Journal of Medicinals), 1971; (91):1098.

[32] Lan Zhou Yi Xue Yuan Xue Bao (Journal of Lanzhou University of Medicine), 1988; 1:36.

[33] Bei Jing Yi Xue (Beijing Medicine), 1988; 2:95.

[34] Hu Bei Zhong Yi Za Zhi (Hubei Journal of Chinese Medicine), 1993; (2):9.

[35] Xin Yi Yao Xue Za Zhi (New Journal of Medicine and Herbology), 1976; 12:26.