Dr. Nase,

Not sure if you saw these articles, but facial heat sensitivity and noxious pain signals in rosacea sufferers are common as you know. In fact, I think you were the first to publish this in two rosacea review articles in Dermatology Times.

I have tried Lyrica and Cymbalta with little help. I have found that oral Rosadyn at higher doses (double-to-triple strength) is actually more effective than both prescriptions. Is that due to the "Proprietary Hypothalamic Blend" in Rosadyn and if so, is there a way to increase Rosadyn's effectiveness even further? These abstracts seem right up your alley as a NeuroVascular Physiologist... help.


(1) J Am Acad Dermatol. 2007 Nov;57(5):800-5. Epub 2007 Jul 20.

Enhanced skin blood flow and sensitivity to noxious heat stimuli in papulopustular rosacea.

Guzman-Sanchez DA, Ishiuji Y, Patel T, Fountain J, Chan YH, Yosipovitch G.
SourceDepartment of Dermatology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.

BACKGROUND: Although patients with rosacea often complain of increased skin sensitivity, there has been no quantitative sensory testing of this phenomenon. Furthermore, cutaneous blood flow in these patients has not been assessed using state-of-the-art laser Doppler imaging (LDI).

OBJECTIVES: To assess heat pain thresholds and skin blood flow using quantitative thermal sensory testing and LDI in patients with untreated rosacea.

METHODS: Of the total 24 subjects enrolled, 8 had papulopustular rosacea (PPR), 8 had erythematotelangiectatic rosacea (ETR) and 8 were control subjects. Subjective burning perception, heat pain threshold, skin blood flow, and skin temperature was assessed in all subjects. In the ETR and PPR groups, two areas were compared: affected and nonaffected.

RESULTS: Heat pain thresholds of areas affected by rosacea were lower than those of nonaffected areas. In addition, subjective burning perception was increased in rosacea patients when compared with control subjects. Although PPR-affected skin had elevated skin blood flow when compared with nonaffected skin, this was not significant for ETR-affected skin.

CONCLUSION: This study showed enhanced sensitivity to noxious heat stimuli in rosacea-affected skin, which was more prominent in the PPR group.



(2) Cutis. 2004 Oct;74(4):257-60.

Noxious sensory perceptions in patients with mild to moderate rosacea treated with azelaic acid 15% gel.
Draelos ZD.

SourceDepartment of Dermatology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA. zdraelos@northstate.net


ABSTRACT AND RESULTS: Patients with rosacea form a unique subset of the sensitive skin population because of the barrier defects inherent in this condition and the increased propensity for burning/stinging from topical products. This propensity for burning/ stinging when medications, skin care products, or cosmetics are applied to the facial skin has been frequently documented but never quantified. The objective of this 2-week study was to determine the prevalence of heightened neurosensory perceptions of burning/stinging in a random population of 40 women with mild to moderate rosacea defined as 15 or fewer inflammatory papules or pustules. Also evaluated was the effect of azelaic acid 15% gel on barrier function and facial stinging utilizing transepidermal water loss (TEWL), corneometry, and lactic acid facial sting tests as noninvasive measurement criteria. At baseline, the incidence of lactic acid stinging among these rosacea subjects was 62.5%, which is substantially higher than observed in the general population. Two weeks after application of azelaic acid 15% gel, no evidence of barrier damage was noted on TEWL or corneometry tests. Moreover, there was no statistical relationship between lactic acid stinging and a stinging response that is occasionally reported with exposure to azelaic acid 15% gel.


----63% of rosacea sufferers reported burning and stinging sensations compared to non-rosacea sufferers. That's a big number.
----BTW, don't ever use Finacea if your skin is predisposed to stinging, burning or hypersensitivity.

RED

Yes, excellent articles. The Vascular Rosacea Subtype is actually more prone to these sensations. Lyrica and Gabapentin don't act on these sensory nerves and thus very few report relief with these medications. These are complex nerves that are classified as sensory non-adrenergic, non-cholinergic nerve fibers and can carry 15 to 20 different heat sensitive neurotransmitters.

Can't block all the transmitters so you either need to block the nerve impulse signal from inducing the release of all these neurotransmitters or block the nerve endings (varicosities) from opening up by blocking G-Protein receptor coupling.

There have been great strides in this area, but they are still one to three years away from something marketable.

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Best,
Geoffrey

Dr. Geoffrey Nase
Ph.D: Neuro-Vascular Physiologist

Email: drnase1000@hotmail.com
Bibliography: http://drnase.com

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