MRCP UK EXAMINATIONS

Detailed explanation-1: -Dopamine from a medication or injection can’t penetrate the blood-brain barrier. That makes it an ineffective treatment. An amino acid called levodopa can help increase levels of dopamine in the brain. If given as a medication, it can cross the blood-brain barrier.

Detailed explanation-2: -The mainstay of current PD treatment are levodopa-based preparations, designed to replace the dopamine in the depleted striatum. As is described above, dopamine itself is unable to cross the BBB and cannot be used to treat PD (2).

Detailed explanation-3: -People with Parkinson’s disease have low brain dopamine concentrations. However, dopamine can’t be given directly as it can’t enter the brain. You may have significant improvement of your symptoms after beginning Parkinson’s disease treatment.

Detailed explanation-4: -Replacing the brain’s dopamine is therefore one of the key treatment strategies to help improve the motor symptoms of PD. Dopamine itself does not cross the blood-brain barrier and therefore can’t be used to treat PD. Instead levodopa, a precursor of dopamine, which does cross the blood-brain barrier is used.