What time of day should i take finasteride?

Finasteride orally is not affected by sweating. So, the answer to your question is no, that’s not even possible.Finasteride does not interact with other medications. Taking it with food or on an empty stomach will not effect how the drug works in any way.

Thank you for your question. You’re asking an interesting question which has been asked of me in my practice about the best time of the day to take finasteride. You’re concerned that if you take it in the beginning of the day since you work out, you may sweat the drug out, and follow up by asking if that is even possible.
I can share with you how I guide my patients who are prescribed finasteride. A little background: I’m a Board-certified cosmetic surgeon and Fellowship-trained oculofacial plastic and reconstructive surgeon. I have been in practice in Manhattan and Long Island for over 20 years. I’m also the founder of TrichoStem™ Hair Regeneration Centers, a system I developed in my practice about 7 years ago as an alternative treatment for men and women with thinning hair using regenerative medicine, which became a significant benefit for patients who are comfortable with taking finasteride.
I do prescribe this drug, and  have been prescribing it since it was introduced in 1997 when hair transplant was a big part of my practice. Going back to the question you have about taking the drug, it is a once-a-day drug. When I talk to my patients about taking this drug, it’s more to establish a habit than it is about the best time of day. The reason is that studies done on compliance with this drug daily have shown a precipitous drop in the second year. For a variety of reasons, close to 50% of men will stop taking the drug in year number two. When we do our medical histories on our patients, very often people will say that “I took the drug for a while, but then I’m not sure if it was working or not, or I was not sure if I was feeling right about it, how the drug might be affecting me. I thought I might have some side-effects.”
Physiologically speaking, you don’t have to be concerned about the drug when sweating. It may give you some peace of mind than to rather take it once a day, take it once before you go to sleep. That way, you have no issues about working when  sweating. It’s more about taking the drug at a regular consistent basis.
Right now, there are a lot of concerns about long-term sexual side-effects. Practically speaking, in my own practice and in the general hair loss treatment community, long-term sexual side-effects are something we have generally experienced with our patients. Patients have mentioned side-effects, and have stopped taking the drug, bt it’s less than 2% in my own practice. This is consistent with the original studies about finasteride, where the active drug group and the placebo group both had less than 2% having sexual side-effects, which makes you at least inquire about the perception. What I often find is patients won’t factor in lack of sleep, exercise, diet and other physiologic issues, but will often see a cause-effect relationship between a drug and how they feel.
We have plenty of patients who have been on the drug for over 15 years. When we treat our patients with Hair Regeneration, many come because they don’t want to take finasteride, or can’t take finasteride. We have been able to establish with Hair Regeneration the ability to stimulate growth of hair that isn’t growing, stopping hair loss progression, and thickening of thinning hairs. Essentially, we can prolong the existing growth cycles, but instead of hair thinning, hair gets thicker, and that’s without finasteride. For 99% of our male and female patients, this is without other pharmaceutical use.
There are some patients who I feel do benefit from the drug, especially those who are younger, and appear to have very rapid hair loss progression. I present to them the possibility of using a DHT blocker to diminish the toxic effect of DHT on their hair, while benefiting from the stimulatory effect of Hair Regeneration, but that’s a separate topic.
Again, the drug itself is absorbed by your body, goes into your circulation, and goes to where the DHT would be blocked, and is blocking specifically an enzyme called 5-alpha reductase. It’s not likely you would be sweating it out. I try to help my patients learn about making this into a habit to stick with it. I always tell my patients that if you take the drug every day for 3 months, regardless of time of day, it becomes a habit, and you’re less inclined to connect a cause-and-effect between the drug and a particular perception. It’s a controversial topic, and for years now, the internet has been exploding with fears about the long-term sexual side-effects, so with Hair Regeneration, we’ve been able to help a lot of patients who are unable to take finasteride.
As far as the drug is concerned, I wouldn’t worry about sweating it out. I suggest you take it at night as it’s a once a day drug. I hope that was helpful, I wish you the best of luck, and thank you for your question.