ONGOING RESEARCH
Trials are currently testing rho kinase inhibitors as a method of vasodilation
MQX-503(nitroglycerin) shows potential in reducing the severity Raynaud's phenomenon
Preliminary reports suggest that botulinum toxin A improves symptoms, symptom, reduces the frequency of attacks, and improve the healing of digital ulcers
Oral phosphodiesterase type 5 inhibitors may be effective in patient with severe and disabling Raynaud's phenomenon, although further studies are needed Only slightly better than nifedipine,25 and because iloprost is more expensive, the European League Against Rheumatism has advised that nifedipine should remain the first line drug for patients with Raynaud's phenomenon.
A double blind multicentre placebo controlled study and randomised double blind study found that orally administered prostaglandins are less effective that intravenous ones , although higher doses may confer benefit.21 Research is currently ongoing into the use of treprostinil, an oral prostaglandin analogue.Phosphodiesterase type 5 inhibitors (sildenafil, tadalafil, and vardenafil)- phosphodiesterase type 5 breaks down cGMP in endothelial cells. Inhibition of this enzyme increases the amount of cGMP available to promote vascular smooth muscle relaxation and blood flow. A randomised double blind placebo controlled fixed dose crossover study and two case series found a decrease in the frequency and severity of attacks in patients treated with oral sildenafil but not tadalafil compared with placebo. These inhibitors score and ulcer healing.26-28 The benefits of these orally delivered and well tolerated drugs suggest that they may be an effective treatment for patients with severe and disabling Raynaud's phenomenon, although further studies are needed