Tymoshenko, who is still in jail, also alleged physical mistreatment, but that complaint was not upheld by the European Court of Human Rights (ECHR).
She was jailed for seven years for abuse of office over a gas deal. Tuesday's verdict does not overturn her prison sentence. The ECHR will examine that verdict later, in a separate case.
In 2009, she signed a 10-year contract for the supply of Russian gas to Ukraine. At her trial two years later, prosecutors argued that she had not obtained the approval of her cabinet to sign the deal, and that it had proved ruinous for the Ukrainian economy. The Strasbourg-based ECHR found that Tymoshenko's detention ahead of her trial had violated her right to liberty and security because it had been ordered for an indefinite period of time.
A complaint that Tymoshenko had been denied proper medical treatment in detention was thrown out by the ECHR judges. On the contrary, they found that the local authorities "had invested efforts far beyond the normal healthcare arrangements available for ordinary detainees in Ukraine". They also threw out an allegation that Tymoshenko had been beaten during a transfer from prison to hospital in April 2012, pointing out that she had refused to undergo a full forensic examination at the time.