At the time, I had been planning to practice medicine. Seven years later, I have my medical degree but I’ve built a career as an entrepreneur. And while my journey may be unique, the lessons I’ve learned in the process of starting a company can be applied to anyone looking to pursue a personal or professional goal.

Let me start by going back to the February 2009 morning that changed my life. I woke up early that day, put my feet on the floor, and was immediately overwhelmed by a crushing headache unlike anything I had experienced before. Making my way to the bathroom, I slammed my shoulder into the door frame. Half of my visual field was gone. Upon gobbling down pain relievers, I curiously noticed my left ankle had collapsed in on itself.

With enormous effort I straightened my ankle, stumbled toward the bed and crumbled onto it. Within seconds, I could not wiggle a finger or toe on my left side.

I called for my roommate, a fourth-year medical student, who initially poked fun when I told him I was having a stroke (hypochondria is common among medical students, and I had just completed a neurology rotation). But when he came into my room, he took one look at my face and dialed 911.

At the hospital, nobody knew what caused the stroke — they simply don’t happen to healthy 24-year-olds. After weeks of tests, blood samples, exams and imaging studies, a team of specialists determined it stemmed from poor circulation flow caused by an acute case of dehydration.

First-year med students are not known for their healthy nutrition habits, and I was no exception. In the weeks leading up to exams, it wasn’t unusual to study 16 hours a day. I’m not much of an eater on a good day, and during that time I ate anything I could grab, which was very little. I drank even less.

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I had no idea dehydration could cause a stroke, and neither did the doctors who treated me, because the incidence of stroke-related dehydration is so low.

Thankfully after several months of physical therapy, I made a full recovery, and graduated from medical school in 2013. But I decided to put practicing medicine on hold.

My experience, coupled with my newfound knowledge about the cause of my stroke, took me on a quest to develop hydration-sensing technology that could prevent others from experiencing the dangerous effects of dehydration.

I enlisted a team of top medical doctors, sports scientists and medical device engineers. Together, we spent more than four years studying hydration, culminating in a patented technology that is the foundation for the wearable hydration monitor we’ve developed called LVL that will come to market in summer 2017. Earlier this year, we raised $1.2 million on Kickstarter, far surpassing an initial $50,000 goal.

It’s been a long journey, and along the way, I’ve learned a great deal – about myself, about being an entrepreneur and about the dedication, perseverance and sacrifice it takes to succeed when building a fledgling business. Whether you are embarking on a professional or personal venture, here are three ways to approach your goal:

— Sometimes you need to let go. Goals evolve over time. As a physician, my father saved lives every day, and as far back as I can remember, I wanted to be like him. But my stroke touched me so directly and so dramatically that I channeled my lifelong passion for practicing medicine into helping people on a larger scale. Rather than impacting hundreds or maybe thousands of lives as a doctor, I’m hoping to make life better for millions.

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— Value teamwork. Entrepreneurs, like doctors, must have faith in their teams. Solving hard problems is not done by a single person but by a multi-disciplined, high-functioning team working together with a single vision and purpose. In the medical field, this is part of an approach we call “just culture.” We critique each other and ourselves without ego, sharing our mistakes so that others may learn from them and avoid duplication moving forward.

— Learn to thrive under crushing uncertainty. Any business you start must grow out of something you love, because there will be dark days. And they could string into dark weeks and dark months. Nonetheless, if your vision is worth anything, it must be all consuming. Success is not an accident or a guarantee. Dedicating your heart, mind and soul to the goal is the only way to persevere.

Now, go have something to drink.

Dustin Freckleton is the founder and CEO of BSX Technologies.