Darlene tried to follow the doctor’s instructions, but the light he’d shone in her right eye made her immediately tear up and want to blink. Whatever the answer was for her recent spate of migraines, it wasn’t this. The light felt as if it pierced her, sending a spike of pain toward the back of her head, making her wince.
The doctor wrinkled his forehead then blessedly turned the light off.
“There’s nothing I can see that’s of concern, at least in terms of the health of your eyes. There’s a medication I can give you that you take at onset of one of these migraines and the symptoms can be reduced or stopped altogether.”
That sounded just fine to Darlene. The migraines had become interruptive to her daily life, causing bright spots in her vision and incapacitating her. They hit out of nowhere and lately the effects on her vision were worsening. Sometimes her vision was clouded completely, as If everything was covered in a grey mist. They affected her emotionally as well, causing her strange sensations of doom or panic. She’d try just about anything at this point. She thanked her doctor, heading downstairs to fill her new prescription. She wanted to be home in bed feeling sorry for herself.
That’s exactly where the next one found her. Laying in bed trying to read and relax, a pinpoint of light started at the center of her eyes and grew until she had to put the book down. She pulled the new bottle of
pills from her nightstand and dry washed it, hoping to stop the bulk of it from happening.
Darlene laid back and hoped for the best. Slowly the visual disturbance abated and her vision went back to normal. She was able to finish the chapter she’d been reading with no further side effects. No spike of pain, no foggy vision, just as the doctor said was possible. She was immensely relieved.
The next morning as she dressed for work she was hit with a spike of pain first, which was unusual. The visual symptoms usually heralded the start of it all. She doubled over from the pain and sat down hard. She reached blindly for her pill bottle but it rattled to the ground and rolled under the bed just in time for the foggy vision to set in.
She closed her eyes and that familiar feeling of doom crawled across her skin. She felt as if she wasn’t alone. She cursed under her breath. Then sensed movement.
She tried to scream but nothing came out. Instead the thick grey mist enveloped her, pouring into her mouth. She choked. Was this real? How could side effects from a migraine be so intense? She scrabbled for her bottle, feeling blindly under the bed. She finally secured them and popped the lid open, pouring one into her mouth. The fog lifted, and though she was shaken, she continued her day as normal.
She managed an entire workday without any symptoms, which was a huge relief. She got home, cooked herself a meal and then showered. When she walked into her bedroom, it was as if the fog from that morning had been waiting for her. No preamble pinpoint of light, no sharp pain, just an all encompassing fog.
She sensed movement again, the flapping of some gigantic thing’s wings. Hot breath and a foul, rotting smell that she could almost taste.
“This can’t be real!” She screamed, trying to ward it off. Maybe it hadn’t been migraines all along, maybe she had been losing her mind and here and now she’d lost the last of it. She stumbled to her bed by feel and threw herself into it, sobbing. She had her eyes closed as tight as she could. When she opened them the fog had again disappeared. She heaved a great sigh in relief.
From above a great scaly mouth opened, baring it’s teeth.
Disremembering
Spreading the Writer's Word 
Excellent!
Oof, I’ve had my fair share of migraines, so the creeping dread in your story was very real to me – good work.
It’s a good thing for us all that this is NOT a real side effect of a migraine. One has enough to deal with. Good one!!