text: The United States has ostensibly exempted humanitarian items from sanctions, but in practice the prohibition against business with Iranian banks and the reduction in issuance of certain medical export licenses by the United States Treasury Department enforcement agency have caused difficulties in Iran.  For example, Iran faces a critical shortage of spare parts that are needed to repair dual-use equipment used to produce medicine.  Sanctions have also prevented Iran from procuring active ingredients necessary to manufacture locally produced medicine to treat asthma, cancer, and multiple sclerosis.
  In December 2020, according to the central bank chief of Iran, Iran could not pay for a COVID-19 vaccine because of U.S. sanctions against Iranian banks. In March 2020, during the first wave of the pandemic, the United States blocked Iran's request for an emergency $5 billion IMF loan.
  After the United States withdrew from the 2015 Iran nuclear deal, many banks and businesses worldwide, including pharmaceutical and medical companies, decided not to conduct any business with Iran due to U.S. sanctions.
  Impact on overseas students
  As of December 2018, United States sanctions were reportedly affecting hundreds of Iranian university students in the United Kingdom, preventing them from being able to readily pay their tuition fees and forcing them to choose between abandoning their studies or using dangerous means to transfer funds.
  Exceptions
  In December 2010 it was reported that the United States Department of the Treasury's Office of Foreign Assets Control had approved nearly 10,000 exceptions to U.S. sanctions rules worldwide over the preceding decade by issuing special licenses for American companies.
  European and United States sanctions do not affect Iran's electricity exports, which creates a loophole for Iran's natural gas reserves.