Is it possible to declare option inside drupal_add_js?
You can try something like

$external_js = array(
  '#markup' =&gt; '&lt;script type="text/javascript" src="//platform.example.com/api.js"&gt;
    api_key:   [key]
  &lt;/script&gt;',
);

drupal_add_html_head($external_js, 'my_module');