How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dr. Brims Your Own Question
Dr. Brims
Dr. Brims, U.S. Licensed Physician
Category: Health
Satisfied Customers: 9605
Experience:  U.S. Licensed Physician, general surgery and internal medicine experience
14307416
Type Your Health Question Here...
Dr. Brims is online now
A new question is answered every 9 seconds

Why does the effect of caffeine vary from day to day? Some

This answer was rated:

Why does the effect of caffeine vary from day to day? Some days coffee perks me up and gives me high alertness, other days a few sips and I suddenly want to fall asleep, like I've been drugged.

Dr Brims :

Hello, welcome to the site! My name isXXXXX and I will try to assist you with your medical question, and any medical information you seek

Dr Brims :

May I ask if you have any medical conditions or take any medication?

Customer:

Just a mild, year-round sinus allergy for which I take Qnasil nasal spray.

Dr Brims :

Okay, how much sleep do you get every night?

Customer:

It varies but generally around 8 hours, give or take an hour.

Customer:

It's usually when I didn't sleep well that the coffee seems to have this knock-out effect. I'm just confused why it seems to assist my fatigue instead of fighting it

Dr Brims :

Okay, this is a sign that your body is very tired, and the caffeine you are drinking may not be adequate, because the body develops a tolerance to it

Customer:

I usually only drink one cup a day. But on these sleepy days no matter how much I drink I just get more and more tired.

Customer:

I understand that coffee can't instantly erase a bad night's sleep but I can't figure out why it seems to make it WORSE

Dr Brims :

It may be a sign that your sinuses are congested, or that you have sleep apnea making you tired

Customer:

But how does that relate to coffee?

Dr Brims :

The coffee may increase your metabolism and augment the feeling you have of drowsiness

Customer:

Hm. Ok. Interesting. Thanks.

Dr Brims :

You're quite welcome

Dr Brims :

If you have any questions in the future, you may request me "Dr Brims" and I will be happy to chat with you

Dr. Brims and 5 other Health Specialists are ready to help you