To make it simple, Levodopa is the precursor of Dopamine and it's used to treat Parkinson's disease. (We don't directly use dopamine because dopamine can't cross our blood-brain-barrier, so, it won't be effective to be taken orally)
pyridoxine (vitamin B6) can decrease the effect of levodopa.
Levodopa itself is not well tolerated, which is why it is combined with carbidopa. Carbidopa decreases peripheral metabolism of levodopa, which allows for lower doses of levodopa and less-severe side effects.
Although levodopa can cross our BBB, but it will be decarboxylated to dopamine peripherally before reaching our CNS - only small amount of Levodopa will be left and available to pass our BBB.So, instead of giving levodopa in high dose (which can cause lots of side effects), we give levodopa with peripheral decarboxylase inhibitors (e.g. carbidopa, benserazide) which can inhibit decarboxylation of levodopa in GIT and peripheral tissues. (By combining levodopa and peripheral decarobxylase inhibitors, we will have less side effects too)
levodopa
yes
levodopa
L-dopa
This may occur after five to 10 years or more of successful levodopa treatment.
Early on in PD, symptoms can be effectively treated with medication, especially levodopa and the dopamine agonists (drugs that act like levodopa).
Bromocriptine (dopaminergic agonist drug) has longer duration of action than levodopa (dopamine precursor).
give Domperidone
Levodopa is used to treat symptoms of Parkinson's disease, such as tremors, stiffness, and slowness of movement. It works by increasing dopamine levels in the brain, which helps to improve motor symptoms associated with the disease.