Trends come and go, but the allure of thick, lush hair is eternal. That desire has only been amplified by the pandemic, going by InStyle readers' buying habits — and it makes sense, especially considering the effect of COVID-19 on hair loss (and everything else). While there are tons of castor oil-infused treatments out there, if you want serious results, dermatologists and shoppers say you can't do better than a minoxidil product like Nioxin's Hair Regrowth Treatment.

If you're not familiar with the ingredient, think of it as the retinol of the hair growth world: Powerful and clinically proven, it's the gold standard for triggering thickness, used in products like Rogaine. "Minoxidil has long been the mainstay for hair regrowth," dermatologist Dr. Michele Green, MD, tells InStyle. "Topical minoxidil works well for both men and women on its own, and in combination with other treatments. I recommend using topical minoxidil for all of my hair loss patients after a consultation."

Green adds that Nioxin will work for women who are experiencing all different types of alopecia, from female pattern to telogen effluvium — and shoppers say the results are astounding. "I tried vitamins, various shampoos, etc., and nothing was working," wrote a 48-year-old with thinning hair. "I've been using it two times a day for a month, and I'm thrilled with the progress. Easy to use liquid that you rub in well. No odor and no side effects for me, other than more hair."

Shop now: $35; amazon.com

Other people echo the enthusiasm, highlighting that where other minoxidil treatments can cause shedding at first, Nioxin doesn't. After a couple of months, a 69-year-old shopper reported, "There has been no shedding, and I have over ¼-inch growth of fine hair. I am so pleased. I tried everything." Even those with naturally thin hair said that when their hairline started receding, they turned to the treatment — and saw "it all grow back."

Timeline-wise, multiple people second that they saw "noticeable" hair growth after a month of using the treatment. But according to some, results can be even faster: "I bought it and my edges have miraculously grown overnight, it seems. They are thick and strong." It varies, though; another reviewer said that two weeks of application "closed up the big bald spot I was getting in the center of the crown of my head."

Regardless, the longer you use it, the greater results you see. "Made such a difference," a last shopper wrote. "My hair was thinning fairly badly. I debated trying this for months, but finally gave in — and I'm so glad I did. Within a month, everyone could tell a difference. It's been a little over two months, and I am no longer embarrassed to wear my hair down. If you're second guessing this, don't. It really does help!"

If you're bored out of your mind going on year three of living la vida indoors and would now watch paint dry, consider watching your hair grow instead. All signs point towards Nioxin offering a risk-free path to more hair, so get a bottle for $35 on Amazon.