I wrote to my MP about this (together with others writing to their own GP). Some time ago there was a shortage of it and again we all wrote to our MP's and it was finally agreed that the pharmaceutical company could buy it from Germany and then sell it on to the chemists but the chemists were not allowed to source it themselves. This is the reply my MP received from Jeremy Hunt:-
With regard to the price of liothyronine (T3), in England, the selling prices of generic products are not controlled. Instead there is reliance on there being a competitive market to keep prices down, to delivery value for money for the NHS. However as there appears to be only one supplier of this medicine, there is no competition in the market. Whilst we have legislative provisions to intervene with regard to prices of medicines, any investigation would require detailed knowledge of the company's business to be able to make a judgement as to whether the price is justified.
International price comparisons for medicines need to be made with caution, particularly when used to compare prices over time. The comparisons can be significantly affected by the relative level of sales in each country of the products used in the comparison, the legal status of the medicine, movement in exchange rates and the proportion (and mix) of medicines expenditure included in the analysis. These vary from country to country and over time. Relative positions, particularly between European countries, will also be affected by the development of different price control policies in these countries.
Healthcare professionals in primary care have a duty of care and decisions should not be made entirely on the basis of cost of the medicine. If a patient's local clinical commissioning group (CCG) decides, on the basis of rational, proper consideration of the evidence, that a treatment requested by the patient and their doctor should be provided, patients must be provided with the reasons for that decision in writing.
Patients can appeal against this decision through their clinician or by contacting their CCG directly to make a formal complaint.
I hope this is helpful
Jeremy Hunt