We are reporting a COVID-19 positive patient who developed diplopia and was found to have an isolated abducens palsy. We reviewed the available English literature of cranial mononeuropathy as a possible manifestation of COVID-19 infection.It is a rare presentation of COVID-19.

We are reporting a case of Guillain- Barré syndrome seven days after the first dose of Pfizer-BioNTech COVID-19 Vaccine. As this vaccine is still under investigation, reporting possible rare side effects is essential. In this case, the temporal relationship was suggestive of a vaccine-induced cause.

This is a case of recurrent episodes of headache and cyanosis who has never been diagnosed despite frequent visits to the hospital. After excluding cardiopulmonary causes, methemoglobin levels were found to be high, without exposure to any offending agent. Also, we did a literature review about congenital methemoglobinemia.