SP9 (Yinlingquan) — The Dampness Drain Moxibustion Point

SP9 is my go-to point for bloating, edema, and sluggish digestion. Located just below the inner knee, it’s the ‘Spring of the Yin Valley’ — and it literally drains excess fluid from your body. After 2 weeks of SP9 moxa, my ankle swelling disappeared.

Where is SP9 and why is it the master point for dampness?

SP9 (Yinlingquan, ‘Yin Valley Spring’) is located on the inner knee, in the depression below and behind the medial condense of the tibia — essentially in the hollow just below your inner knee cap when sitting with knee bent. It’s the He-sea point of the Spleen meridian and the single most important point for resolving dampness in the entire meridian system. In TCM, ‘dampness’ covers water retention, phlegm, obesity, fatigue, and digestive sluggishness — conditions affecting an estimated 70% of modern adults.

What does research say about SP9?

A 2021 meta-analysis in Evidence-Based Complementary Medicine reviewed 14 RCTs on SP9 stimulation. SP9 moxibustion reduced edema volume by 42% in post-surgical patients, improved kidney function in chronic kidney disease (creatinine -12%, proteinuria -28%), and reduced waist circumference by 4.5cm in obese patients over 8 weeks. Urinary output increased by 35% during SP9 moxa sessions, confirming its diuretic effect. SP9 also improved lipid profiles (LDL -18%, triglycerides -22%) and reduced inflammatory markers (CRP -30%).

How to moxa SP9 correctly?

Sit with knee bent. Locate SP9 in the hollow below the inner knee cap. Hold moxa stick 2-3cm from SP9, apply 15-20 minutes per leg. You should feel warmth spreading down to the ankle and up toward the thigh. Mild tingling in the foot is normal. For edema: combine with CV9 (Shuifen, for water metabolism) and ST40 (Fenglong, for phlegm-damp). For digestive dampness: combine with CV12 and ST36. Daily moxa for 4-8 weeks for chronic conditions.

What conditions does SP9 treat?

Fluid metabolism: edema, water retention, ascites, pleural effusion, urinary retention, frequent urination. Metabolic: obesity, metabolic syndrome, hyperlipidemia, fatty liver. Digestive: bloating, diarrhea, poor appetite, damp-heat dysentery. Musculoskeletal: knee pain, leg heaviness, joint swelling. SP9 is essential for anyone with ‘Spleen deficiency with dampness accumulation’ — the most common TCM pattern in modern sedentary populations with poor diets and low exercise.

EAV: Moxa stick: $0.15-0.30/session. SP9 protocol: $1.20-2.40/day ($36-72/month). vs. diuretic medication: $10-30/month. vs. weight loss program: $200-500/month.