While Americans are confronting an epidemic of prescription drug abuse, particularly for addictive painkillers, the reverse problem prevails in much of the world.

Many ill people with a legitimate need for drugs like oxycodone and other narcotics known as opioid analgesics cannot get them and are suffering and dying in pain, according to health officials, doctors and patients’ rights advocates.

In Russia, India and Mexico, many doctors are reluctant to prescribe these painkillers, fearful of possible prosecution or other legal problems, even if they believe the prescriptions are justified.

In Kenya, health officials only recently authorized the production of morphine, one of the most effective drugs for pain relief, after criticism that it was available in only seven of the country’s 250 public hospitals. In Morocco, the advocacy group Human Rights Watch reported in February, only a small fraction of physicians are permitted to prescribe opioid analgesics, which the country’s law on controlled substances identifies as poisons.