A reading of 140/100 mmHg is high blood pressure. It falls into stage 2 hypertension, the more serious of the two hypertension stages, under current American Heart Association and American College of Cardiology guidelines. Both numbers are elevated: stage 2 begins at 140 systolic (the top number) or 90 diastolic (the bottom number), and your reading exceeds both thresholds.
This is not a medical emergency, but it does need attention. A reading this high, if confirmed on repeat measurements, typically warrants medication in addition to lifestyle changes.
What the Two Numbers Tell You
The top number (140) measures the pressure in your arteries when your heart beats. The bottom number (100) measures the pressure between beats, when your heart is resting. In a healthy reading, the top number stays below 120 and the bottom stays below 80.
A diastolic reading of 100 is worth paying special attention to. High diastolic pressure means your blood vessels are under significant strain even when your heart is at rest. Over time, this raises your risk of heart attack, heart failure, and death from cardiovascular disease. These risks are greatest for women and people under 60. At 100, your diastolic pressure is well above the hypertensive threshold of 80 but still far below the emergency zone of 120 or higher.
Why One Reading Isn’t Enough
Blood pressure fluctuates throughout the day based on stress, caffeine, physical activity, and even the anxiety of having it measured. A phenomenon called white-coat hypertension can push readings above 140/90 in a clinical setting even when your pressure is normal the rest of the time. Guidelines recommend confirming elevated office readings with measurements taken outside the clinic before starting treatment.
If you’ve gotten a single reading of 140/100, the next step is tracking your numbers at home over several days. When you do, follow these practices for accurate results:
- Timing: Measure at least twice daily, once in the morning before eating or taking medication and once in the evening.
- Preparation: Sit quietly for a few minutes first. Don’t talk during the reading.
- Arm position: Rest your arm on a table at heart level. Place the cuff on bare skin, not over clothing.
- Repetition: Take two or three readings each time and use the same arm consistently.
If your home readings consistently come back at or above 140/90, the elevation is real and worth discussing with a healthcare provider. If they’re consistently below 140/90 at home, you may have white-coat hypertension, which carries less risk but still deserves monitoring.
Why Stage 2 Hypertension Is Taken Seriously
High blood pressure usually produces no symptoms at all. The CDC confirms that most people with hypertension don’t know they have it, and measuring your blood pressure is the only way to find out. You can feel perfectly fine at 140/100. That silence is part of the danger: the damage happens gradually, inside your blood vessels and organs, over months and years.
Untreated hypertension is one of the strongest risk factors for stroke. Research published in the AHA’s journal Stroke found that untreated high blood pressure increased the risk of hemorrhagic stroke (bleeding in the brain) by 3.5 times compared to people with normal pressure. Hemorrhagic strokes, while less common than clot-based strokes, carry a mortality rate of 40 to 50 percent. The same research estimated that roughly one in four hemorrhagic strokes among people with high blood pressure could have been prevented with treatment.
Beyond stroke, sustained high pressure damages artery walls, forces the heart to work harder (eventually thickening and weakening it), and harms the kidneys, eyes, and brain over time.
Treatment at This Level
The 2025 AHA/ACC hypertension guideline is clear: all adults with confirmed blood pressure at or above 140/90 benefit from medication. At stage 2, the recommendation is to start two blood pressure-lowering medications from different classes, ideally combined in a single pill. Starting with two medications instead of one gets blood pressure under control faster and improves the likelihood of sticking with treatment.
Medication works alongside lifestyle changes, not instead of them. The most well-studied dietary approach is the DASH diet, which emphasizes fruits, vegetables, whole grains, and lean protein while limiting saturated fat and added sugar. In clinical trials, the DASH diet lowered systolic pressure by about 11 mmHg and diastolic pressure by about 4.5 mmHg, independent of sodium reduction. That’s a meaningful drop, roughly equivalent to what a single blood pressure medication achieves, though at 140/100 it likely won’t be enough on its own.
Other lifestyle changes that reliably lower blood pressure include regular aerobic exercise (at least 150 minutes per week of moderate activity), reducing sodium intake, limiting alcohol, maintaining a healthy weight, and managing stress. Each of these contributes a few points of reduction, and the effects add up.
When It Becomes an Emergency
A reading of 140/100 is not a hypertensive crisis. That threshold is 180/120 or higher. If you ever see a reading at or above 180/120 along with symptoms like chest pain, severe headache, confusion, vision changes, or shortness of breath, call 911. That combination signals possible organ damage and requires immediate treatment.
If your reading hits 180/120 but you have no symptoms, rest for several minutes and measure again. If it stays elevated, seek medical care that day. If it comes down, contact your provider to let them know.
At 140/100, you have time to confirm the reading, start a home monitoring routine, and work with a provider on a treatment plan. What you don’t want to do is ignore it. The gap between 140/100 and a dangerous level narrows faster when blood pressure goes unmanaged.