Cold Sweat or Hot Flash?When Sudden Sweating Is a Heart Attack Warning Sign in Women

A sudden drench of sweat after 50 is usually a hot flash. But “sweating a lot for no reason” is also on the National Heart¹, Lung, and Blood Institute’s list of heart attack symptoms.¹ The federal Office on Women’s Health² lists the “cold sweat” as a heart attack sign too, under the heading “Cold sweats, and you know it’s not menopause.”²

How a hot flash and a warning sweat compare

The two can feel alike. A hot flash can end in “a cold, clammy feeling,” and it can bring heart palpitations.⁴ What separates them is usually what comes with the sweat.

	A typical hot flash	Sweat that means call 911
How it starts	A sudden wave of heat in the upper body, then flushing45	Heavy sweating for no reason1
How long	30 seconds to 5 minutes; 4 minutes on average4	Keeps going, or comes with other signs below
What comes with it	Red face and neck, red blotches on the chest, back and arms, then a cold, clammy feeling45	Chest pain, heaviness or pressure; pain in one or both arms, the back, shoulders, neck, jaw or above the belly button; nausea or vomiting; lightheadedness or sudden dizziness1
Common triggers	Spicy food, alcohol, caffeine, stress, a hot room5	None you can point to1

This table is a guide, not a test. A woman who has hot flashes can also have a heart attack. When the sweat comes with any sign in the right-hand column, treat it as an emergency.

Why the other signs matter for women

• Chest pain is still the most common symptom in women and men.²
• But many women don’t have it. In a US registry of 1,143,513 people hospitalized with a heart attack between 1994 and 2006, 42% of the women arrived without chest pain, compared with 31% of the men.⁶ The difference between women and men was largest at younger ages and got smaller after 65.⁶
• Sweating may point to the most serious kind of heart attack. A study at one hospital in Ajmer, India, followed 12,913 patients admitted with heart symptoms.⁷ When typical chest pain came with sweating, it turned out to be a STEMI, the type caused by a fully blocked artery, 76% of the time. Typical chest pain without sweating was a STEMI 23% of the time.⁷
• Unusual tiredness, sometimes lasting days, is more common in women.¹

What this research can’t tell you

• The registry recorded whether chest pain was present. It didn’t count how many women had a cold sweat.⁶
• The Ajmer study included only people already admitted to a cardiology unit. Its numbers can’t tell you what a sweat at home, with no other symptoms, means.⁷
• Most drenching nights have other causes. Our guide to night sweats covers them.

What to do

• Call 911 if sweating comes with any warning sign above, even if you aren’t sure it’s your heart. Acting fast can limit damage to the heart.¹
• Don’t drive yourself, and don’t let someone else drive you.¹
• Don’t wait to see whether it’s menopause. Only an emergency department exam can rule a heart attack in or out.²
• If you take insulin or diabetes pills, sweating with shakiness or hunger can be low blood sugar. See our diabetes night sweats plan.
• For hot flashes with no warning signs, book a regular visit. Start with what causes hot flashes and whether menopause raises heart disease risk.

Try, at your next checkup: “Last month I had a sudden cold sweat with nausea and felt lightheaded, and it passed on its own. Could that have been my heart, and should I be checked?”

Arms Up puts sweating with chest pain, nausea, dizziness or lightheadedness at the top of its Red-Flag List in Chapter 3, marked as an emergency. Its Fresh Log helps you record ordinary sweats by zone and time, so one that comes out of nowhere stands out. See the book.