Author: Rainier Guiang MD

Rainier Guiang, MD is a board-certified Anesthesiologist and Pain Medicine physician (American Board of Anesthesiology) and the Director of Regenerative Medicine at University Pain Consultants, which he co-founded in 2007. Practicing across six locations in California's Inland Empire, he focuses on evidence-based, non-surgical approaches to chronic pain, including PRP/PRF therapy, IV ketamine infusion, and low-dose naltrexone (LDN). Dr. Guiang completed his anesthesiology residency and pain medicine fellowship at Case Western Reserve University / University Hospitals of Cleveland, earned his MD from the American University of the Caribbean, and holds a BS in Biology from UCLA. He is committed to helping patients understand their options through clear, research-grounded education.

Non-Opioid IV Infusions for Pain: Lidocaine, Magnesium, Toradol & the Myers’ Cocktail

If you live with chronic pain, nerve pain, or migraines that oral medications haven’t controlled, intravenous (IV) infusion therapy offers another route to relief. By delivering pain-relieving and anti-inflammatory medication directly into your bloodstream, IV infusions act quickly and reach areas that pills struggle to. Just as importantly, the four infusions below are non-opioid and […]

Cortisone Shots vs. PRP: Are Steroid Injections Bad for Your Joints Long-Term?

A board-certified pain physician on what repeated cortisone injections do to your joints over time — and why PRP may be a healthier, longer-lasting alternative.

Red Light Therapy for Peripheral Neuropathy: What the Evidence Shows

A board-certified pain physician on what red light therapy (photobiomodulation) can and cannot do for diabetic, chemotherapy-induced, alcoholic, and other peripheral neuropathy.

IV Ketamine for Treatment-Resistant Depression: What the Research Shows

Some people move through one antidepressant after another and never really get their footing back. When two or more honest attempts with standard medication haven’t helped, that has a name — treatment-resistant depression, or TRD — and it’s exactly where IV ketamine has shifted the conversation over the last decade. The thing that grabbed everyone’s […]

PRP for Hair Loss: Does It Really Work? What the Research Shows

PRP for hair loss has become one of the most popular non-surgical options for thinning hair — but does it actually regrow hair, and is it worth the cost? Below, Dr. Rainier Guiang, MD, a board-certified physician at University Pain Consultants in Riverside and Menifee, California, reviews what the published evidence shows and who tends […]

PRP for Knee Pain: Does It Really Work? An Evidence-Based Guide

Platelet-rich plasma (PRP) for knee pain has moved from the sidelines of sports medicine into mainstream orthopedic and pain practice. If you have knee osteoarthritis or a chronic knee injury and want to avoid — or delay — surgery, you have probably come across PRP as an option. But does it actually work, and is […]

IV Ketamine Infusions for Chronic Pain: A Breakthrough for When Nothing Else Has Worked

IV ketamine infusion therapy offers a fundamentally different approach to chronic pain — targeting the overactive pain pathways in the nervous system itself. Dr. Rainier Guiang explains how ketamine works, what conditions it treats including CRPS and neuropathic pain, and what to expect as a patient at University Pain Consultants.

Low Dose Naltrexone for Fibromyalgia: What a Pain Specialist Wants You to Know

Pain specialist Dr. Rainier Guiang explains how low dose naltrexone (LDN) works for fibromyalgia — the mechanism, the evidence, dosing protocol, side effects, and who is a good candidate.