Ah, spring: the time of year when the weather starts getting warmer, we start getting sweatier, and we may find ourselves reaching for our deodorant more often. Don’t get us wrong—sweating is a perfectly normal bodily function, and nothing to be ashamed about. But, if you’re paying good money for deodorant, then you want it to do its job. So, how do you make the most out of your stick, spray, or roll-on? And more specifically, how much deodorant should you put on in order for it to be effective? Don’t sweat it: we have all the answers.

How Much Deodorant Should You Put On?

While each of the dermatologists we interviewed noted that there is no “standard dose” of deodorant, they all provided the same general guidelines: applying two or three swipes of a stick or roll-on deodorant, two or three spritzes of a spray-on deodorant, and a pea-sized amount of cream or gel deodorant should do the trick. “While the amount of deodorant each person needs will vary, on average, most people will require a few swipes or a few seconds of spray,” says Michele Green, MD, board-certified dermatologist. “The goal is to achieve full coverage without causing product buildup.”

The Best Time to Apply Deodorant

According to Kristina Collins, MD, double board-certified dermatologist, it’s not about how much deodorant you put on, but rather, when you apply it. “The quantity of deodorant is probably less important than the timing, as application timing before a person has begun to sweat is typically more effective,” she says. “Antiperspirants should ideally be applied at night. Deodorants are generally applied in the morning or before leaving the house.” 

Clinical-strength deodorants are applied morning and night, says Jeannette Graf, MD, board-certified dermatologist and assistant clinical professor of dermatology at Mt. Sinai School of Medicine. It also depends on what you’re doing. “If you are engaging in heavy activity, if you tend to sweat more than average, or notice a stronger body odor, you can instead reapply your deodorant every few hours or consult your dermatologist for a stronger deodorant,” Graf says.

Deodorant is most effective when it’s applied to fresh, clean, and dry skin instead of on top of other products—like lotions, says Anna Chacon, MD, board-certified dermatologist. “That way it can stick directly to the skin’s surface to do its job,” she says. “It will not be as effective when applied to wet skin.”

The Active Ingredient to Look For

Meanwhile, James Kilgour, MD, a resident dermatologist at Stanford University says that it’s not the amount of deodorant you put on that makes a difference: it’s the active ingredient. “The most important thing about deodorant is that it needs to contain aluminum in order to be effective,” he explains. “While aluminum-free deodorants have become popular, these are little more than perfume sprays which will only mask body odor, rather than preventing the development of odors and excess sweat.”

Is It Possible to Put on Too Much Deodorant?

Believe it or not, deodorant isn’t the type of product that becomes more effective the more you put on. “Excessive application of deodorant can lead to residue formation, resulting in irritation of the skin or blocking the pores, unsightly white discoloration on fabrics, and possibly poor performance if an excessive amount creates a buildup and prohibits active ingredient penetration,” says Raechele Cochran Gathers, MD, board-certified dermatologist. “The active ingredients must be spread evenly, not piled on top of each other.”

However, from a broader health perspective, overusing deodorant is unlikely to cause significant harm, Kilgour says. “People are often concerned about adverse health effects from exposure to aluminum, because of scary headlines in the media claiming that aluminum could cause [chronic] or neurological diseases,” he explains. “The reality, however, is that there is no evidence to support aluminum causing either of these conditions, even in people with significant occupational exposure to aluminum.” 

Do 48- and 72-Hour Deodorants Really Last That Long?

While certain antiperspirants claim 48- or 72-hour effectiveness, Gathers says that their duration depends on personal sweat rate, activity level, and skin type. “Many users will see the effectiveness diminished from washing, rubbing, and sloughing of the skin,” she says. Plus, as Amy Huang, MD, board-certified dermatologist, points out, all deodorants eventually get rubbed off with friction and constant motion of the arms.

According to Kilgour, the claims of 48-to-72-hour protection are based on laboratory testing—not real-world conditions. In reality, these supposedly long-lasting deodorants likely won’t have that kind of power, especially if you’re bathing regularly, he explains. “For that reason, I generally recommend daily use of an aluminum-containing deodorant, with application performed after showering/bathing for best results.”