Carboxy Therapy

Mechanism of action:

• Based on the Bohr effect: increased CO2 causes hemoglobin to release more oxygen
• CO2 injection causes local vasodilation and increased blood flow
• Enhanced oxygenation stimulates collagen and elastin synthesis
• May trigger VEGF-mediated angiogenesis (new blood vessel formation)
• For fat reduction: may cause temporary adipocyte shrinkage (not cell death)

Key studies:

• Costa et al. (2023): Systematic review of 27 studies on cellulite and striae
• Tabaie et al. (2024): Clinical trial showing significant reduction in periorbital hyperpigmentation
• Lee et al. (2018): RCT showing fat reduction at 1 week but not sustained at 6 months
• Saleh et al. (2020): 8-session protocol improved stretch marks with collagen remodeling

Applications with evidence:

• Dark circles (periorbital hyperpigmentation) - moderate evidence
• Stretch marks (striae distensae) - moderate evidence
• Cellulite - limited evidence
• Localized fat reduction - transient effects only
• Wound healing - emerging evidence

Limitations:

• Most studies are small (10-30 participants)
• Not FDA-approved (as of 2018)
• Long-term durability of results unclear
• Mechanism for fat reduction appears temporary

Standard treatment protocol:

1. Sessions: 6-10 sessions typical course
2. Frequency: Weekly sessions
3. CO2 volume: 10-100 mL per area depending on treatment
4. Flow rate: 20-80 mL/min
5. Temperature: Often cooled (15°C) for comfort

For dark circles:

• Intradermal injection around orbital area
• 10-20 mL CO2 at 20 mL/min
• 4-6 weekly sessions
• Results visible after 3rd session typically

For stretch marks:

• Subcutaneous injection along striae
• Higher volumes (50-150 mL per area)
• 6-8 sessions at 1-2 week intervals
• Combine with topical treatments for enhanced results

For cellulite:

• Subcutaneous injection in affected areas
• 100-200 mL per treatment area
• 8-10 weekly sessions
• Maintenance sessions may be needed

Post-treatment:

• Avoid strenuous exercise for 24 hours
• Mild bruising and swelling normal for 2-5 days
• Results typically assessed 1-2 weeks after final session

Common side effects (expected):

• Pain during injection (main limiting factor)
• Bruising at injection sites (30-45% of patients)
• Temporary swelling/oedema
• Erythema (redness) lasting 1-3 days
• Crackling sensation under skin (resolves in hours)
• Heavy legs sensation (due to vasodilation)

Rare complications:

• Air embolism (if improperly performed)
• Tissue emphysema
• Inadvertent lipolysis in unintended areas
• Infection at injection sites

Contraindications:

• Cardiovascular disease (heart failure, recent MI, unstable angina)
• Respiratory conditions (COPD, sleep apnea)
• Recent thrombosis, phlebitis, or pulmonary embolism
• Pregnancy
• Active cancer or post-cancer (growth-promoting effects)
• Epilepsy
• Severe anemia or bleeding disorders
• Uncontrolled diabetes
• Active skin infection
• Glaucoma (risk of increased intraocular pressure)

Important notes:

• Not FDA-approved
• Must be performed by qualified professional
• Pain is significant - discuss with practitioner beforehand

Ideal candidates:

• Those with stubborn dark under-eye circles
• People with stretch marks (especially striae alba)
• Those seeking non-surgical cellulite treatment
• Patients who haven't responded to topical treatments
• Those willing to commit to multiple sessions

Should skip:

• Anyone with cardiovascular or respiratory conditions
• Those seeking permanent fat reduction (effects are transient)
• People with low pain tolerance (procedure is uncomfortable)
• Those expecting dramatic results
• Anyone unwilling to commit to 6-10 session course

Better alternatives:

• For fat reduction: diet/exercise, or proven procedures like cryolipolysis
• For dark circles: address root cause (sleep, allergies, sun protection)
• For stretch marks: microneedling or laser may have better evidence

What to measure:

• Photography: Same lighting, angle, and distance before each session
• Circumference measurements (if treating cellulite/fat)
• Subjective satisfaction ratings
• Side effect diary

Timeline:

• Initial assessment: Before first session
• Progress photos: Before each session
• Interim assessment: After 4-5 sessions
• Final assessment: 2-4 weeks after last session

Signs it's working:

• Dark circles: Visible lightening after 3+ sessions
• Stretch marks: Improved texture, reduced visibility
• Cellulite: Smoother skin surface
• Skin: Improved texture and elasticity

Red flags:

• Excessive bruising lasting >1 week
• Signs of infection (increasing redness, warmth, pus)
• Persistent numbness or nerve symptoms
• No visible improvement after 6 sessions

Per session costs:

• Small area (eyes): $75-150
• Medium area (face/neck): $100-200
• Large area (abdomen/thighs): $150-300

Full treatment course:

• Dark circles (6 sessions): $450-900
• Stretch marks (8 sessions): $800-1,600
• Cellulite (10 sessions): $1,000-2,500

Cost considerations:

• Usually not covered by insurance (cosmetic)
• Package deals often available (10-20% discount)
• Maintenance sessions may be needed
• Compare to alternatives:
• Laser treatments: $200-500/session
• Microneedling: $200-700/session
• Topical retinoids: $20-100/month

Researchers:

• Dr. Luigi Parassoni - Italian pioneer who developed carboxytherapy in the 1990s
• Dr. Nadia Afsar Kazerooni - Research on periorbital applications

Note: Carboxytherapy is more established in Europe and South America than in the US, where it remains off-label.

Common positive reports:

• "Dark circles noticeably lighter after 4 sessions"
• "Stretch marks less visible and skin texture improved"
• "Results for cellulite better than expected"

Common complaints:

• "Painful - the CO2 injection burns"
• "Expensive for results that may not last"
• "Bruising was significant for the first few days"
• "Hard to find qualified practitioners in the US"
• "Results faded after a few months"

Reddit/forum sentiment:

• Mixed reviews, with pain being the most common complaint
• Better reception for dark circles than fat reduction
• Many note it's more popular/accessible in Europe and Latin America

Often combined with:

• Topical retinoids - Enhanced penetration after carboxytherapy
• Microneedling - Complementary collagen stimulation
• PRP (platelet-rich plasma) - Combined protocols studied for stretch marks
• Fractional CO2 laser - Studies show combination more effective than either alone

Timing considerations:

• Space carboxytherapy 1-2 weeks from other procedures
• Avoid same-day combination treatments
• Complete carboxytherapy course before adding other modalities