Which of the anti-epileptic drugs affect the metabolism of the Pill (oral contraceptive) and what are the implications of this? Which drugs are safe to use in combination with the Pill

Drugs that decrease the effectiveness of the pill are as follows: Phenobarbitone, phenytoin, carbamazepine, oxcarbazepine and topiramate. Due to its decreasing the effectiveness of the pill it may lead to an unwanted pregnancy.

Drugs that are safe to use in combo with the Pill: Valporate, Lamotrigine, Gabapentin, Leviteracetam and Vigabartin.

Can oral contraceptives also affect the effectivity of the anti-epileptic drugs?

Yes, oral contraceptives decrease the serum levels of anti-epileptic drugs for example, Valporate.

How does age affect the kinetics of these drugs (from neonates to old age)

Metabolism of anti-epileptic drugs are slower in neonates than in adults, but metabolism of these drugs is faster in babies and in children than adults. And due to lowered metabolic activity in  geriatrics metabolism does appear to be slower in geriatrics than in adults.

In which cases is plasma blood level monitoring indicated?

it is indicated to see how well a patient’s body tolerates a drug and help a practitioner to identify if any unwanted effects are experienced with the drug. For example, in the case of Valporate and lamotrigine, as valproate deceases the metabolism of lamotrigine which leads to the increased levels of lamotrigine in the blood and in its turn can cause toxicity.