it is used medicinally in China in the same way as Salvia bowleyana and is often confused with it. chemically and medicinally, they're pretty much the same.

relaxes blood vessels, thins the blood to prevent blood clots, prevents atherosclerosis (plaque buildup), and protects the heart from oxidative damage.
good for angina, coronary heart disease, myocardial infarction, post-heart attack recovery, atherosclerosis, hypertension, and general cardiovascular support.

improves blood circulation to the pelvis, relaxes uterine muscle spasms, and reduces inflammation. can help prevent miscarriages.
good for painful periods, missed or irregular periods, post-childbirth recovery, and clearing "stagnation" in the reproductive system.

helps recovery after ischemic stroke by improving blood flow to the brain, protecting brain cells from further damage, and preventing additional clots from forming.

kills cancer cells like breast, lung, liver, colon, prostate, leukemia, and gastric cancers in lab studies.
triggers cancer cell self-destruct, blocks tumor blood supply, and prevents metastasis.

it was found that salvia bowleyana has a higher salvianolic acid B content than salvia miltiorrhiza and may be used as a novel source of this potential anti-gastric cancer compound.

inhibits cell proliferation in head and neck squamous cell carcinoma.
if you can get your hands on salvia miltiorrhiza, do it. here's a full article of some benefits of them: https://pmc.ncbi.nlm.nih.gov/articles/PMC7285817/

anti-inflammatory action documented across multiple inflammatory conditions including rheumatoid arthritis, chronic skin inflammation, and cardiovascular inflammation.

protects the liver from chemical damage, alcohol, and chronic inflammation. prevents scarring (fibrosis).

protects the kidneys, improves renal blood flow, and slows the scarring that drives chronic kidney disease (CKD).

may increase the blood thinning effect of warfarin.

It may reduce midazolam concentrations in blood, decreasing the pharmacologic effects, which can potentially change the effects for many drugs.
different from Dang Shen. Here is a research paper on the similar herbs different genetic properties:
https://www.researchgate.net/figure/Phylogenetic-relationship-between-S-miltiorrhiza-S-bowleyana-and-S-paramiltiorrhiza_fig2_351489841