Your patient is 54 years old, otherwise healthy, and presents with symptoms of achalasia. He has a follow a up appointment with a gastroenterologist in one week but is having severe pain and regurgitation with meals and is not able to move up his appointment. What can you do?
Pneumatic dilation and surgical myotomy are the most effective therapeutic options for achalasia.  However, in selected patients, especially those with early disease or who are not surgical candidates, there may be a role for pharmacologic agents. The most widely used are:
Nifedipine: 10-30mg sublingual 15-30 minutes before meals. In one small prospective manometric study nifedipine SL was compared to pneumoatic dilation and excellent or good clinical results (evaluated by a standardized scale) were observed in 75% dilated and 77% of patients treated with nifedipine with supportive manometric results. nifedipine side effects inlcuded vasoldilation, peripiheral edema, headache, and hypotension with one 1/16 patients unable to tolerate the therapy. 
Nitroglycerine: 0.4mg sublingual 10-15 minutes before meals. Unfortunately 2004 Cochrane Review concluded that the current evidence could not provide any implications for practice, though they did note single reports documenting a “fall in lower esophageal pressure and improvement of radionuclide esophageal emptying compared to baseline.”  Look out for bradycardia, hypotension, edema, headache nausea and vomiting and avoid concomitant use with medications for erectile dysfunction.
Another option that will require a specialist but that may be helpful in a non-surgical candidate is Botulinum Toxin. One review article concluded a single injection was up to 85% effective in the short term, with effect waning to 30% after on year. 
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2) Coccia, G., M. Bortolotti, P. Michetti, and M. Dodero. “Prospective Clinical and Manometric Study Comparing Pneumatic Dilatation and Sublingual Nifedipine in the Treatment of Oesophageal Achalasia.” Gut 32.6 (1991): 604-06. Web.
3) Wen, Zh, E. Gardener, and Yp Wang. “Nitrates for Achalasia.” Cochrane Database of Systematic Reviews Reviews (1996): n. pag. Web.
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