CENTRAL TEXAS (CBS11) – The second medical marijuana dispensary, Compassionate Cultivation, in Texas opened Thursday, making four sales in its first day.

It is the first to offer a location, where epilepsy patients can fill prescriptions for cannabis oil in person.

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One of the first patients to come through the doors was Oscar Wilkens.

The now 2-year-old suffered his first seizure when he was only 5 months old.

“Fell asleep in my lap and woke up having a seizure,” recalled his mother, Christy. “That was just the beginning of what’s been a very long journey for us.”

His parents still don’t know the underlying cause behind his seizures and developmental delays.

“It’s hard… and joyful,” said his father, Todd Wilkens of day to day life with his son.

Oscar Wilkens receives cannabis oil (CBS11)

Physical therapy and diet have helped, but the medication Oscar takes can create complications.

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“It can decrease muscle tone. He already has low muscle tone. It can slow down your thinking and make you tired and groggy. He already has problems with cognition,” said Christy.

Eager to see if cannabis oil could stop his seizures without the serious side effects, his mother today became one of the first people in the state to purchase medical marijuana through a new state-run program.

“I’m happy that this day has finally come for Texas,” she told reporters who witnessed the sale.

Oscar’s neurologist, Dr. Karen Keough, who serves as medical director for Compassionate Cultivation, says patients have been clamoring to try the oil. She warns, though, only 30 to 40 percent may see meaningful benefit and fewer still could see it end all their seizures.

“Probably a realistic expectation? About ten percent will get full control at best. It’s a pretty low number, but if you’re in that ten percent, then that’s awesome, right?” said Dr. Keough.

Thursday evening, Oscar received his first dose.  Now his family waits to see what it does.

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“I’m cautiously optimistic and hopeful it works for him,” said Christy.