Treatment interruptions and inconsistent supply of anti-tuberculosis drugs in the United Kingdom.

Setting: National Health Service (NHS) centres treating tuberculosis (TB) in the United Kingdom.
Objectives: To describe NHS TB treatment centres' experience of obtaining anti-tuberculosis drugs to treat drug-susceptible and drug-resistant TB between 2007 and 2009. In particular: 1) any difficulties experienced in obtaining different drugs; 2) resulting interruptions or alterations in the prescribed regimen; 3) availability of paediatric formulations; and 4) resources available to identify and manage drug shortages.
Design: Questionnaires were sent to pharmacists at 168 treatment centres.
Results: Of the 77 (46%) treatment centres that responded, 63% (48/77) reported difficulties in obtaining anti-tuberculosis drugs. Consequently, 27% had to interrupt the prescribed treatment regimen at least once, whilst 19% had to alter the regimen. Of 55 centres treating multidrug-resistant tuberculosis, 36% reported difficulties obtaining second-line drugs, 16% had to interrupt the prescribed treatment regimen at least once and 5% had to alter the regimen. A lack of licensed liquid formulations for children resulted in 26% of treatment centres using unlicensed, variable-strength liquids and locally prepared suspensions.
Conclusions: Difficulties obtaining drugs to treat both drug-susceptible and drug-resistant disease are common in the UK. There are particular risks for children. Our data identify an urgent need for national strategic guidance to ensure a consistent and reliable supply of anti-tuberculosis drugs.