Welcome to JA and thanks for this question. Im sorry to hear about your friend's symptoms. Sharp sudden pains in this region which are NOT accompanied by sweating, shortness of breath or even radiation of the pain to the jaw or the left arm are more likely to be associated with a muscle spasm or even due to nerve compression in the region. Muscle spasms can occur suddenly and occur repeatedly in many cases and would be diagnosed on a clinical examination. It would be best treated with an increased intake of plain water, cutting back on caffeine, using electrolyte rich fluids like gatorade, using OTC ibuprofen at a dose of 200 mg thrice daily if the pain is persistent and if necessary by using muscle relaxants like tinazidine or flexeril.
The other possibility is that of costochondritis which is a condition in which the cartilages of the ribs are inflammed, this too can cause sudden sharp pains of this sort and over time it can also cause pain while coughing. this would be treated with anti inflammatory agents like ibuprofen.
Now if the pain starts to occur more frequently or changes it character to more of a pressure sensation in the region or causes sweating or shortness of breath or even radiates to the jaw and the left arm then it has to be considered for heart disease. In this scenario a EKG is necessary to rule out heart disease.
For now try the above measures and if they dont help then have this evaluated by taking your friend to the ER.
Do you have any more questions?
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