Cannabis withdrawal can raise blood pressure, and in some people the increase is large enough to matter clinically. The best direct evidence comes from a controlled study of daily cannabis users whose systolic blood pressure climbed by about 10 points on average after they stopped using, with a subset of participants seeing spikes above 20 points. The effect is real, grounded in how the body’s own cannabinoid system regulates blood vessels, and largely absent from the standard lists of withdrawal symptoms that most people encounter online.
What the Numbers Actually Look Like
The most cited study on this topic monitored heavy daily cannabis users across periods of active use and periods of abstinence within a controlled research setting. During cannabis use, the group averaged about 130 systolic and 75 diastolic. During abstinence, those numbers rose to roughly 140 systolic and 82 diastolic. Both changes were highly significant statistically.1PubMed Central. Increased Blood Pressure Following Abrupt Cessation of Daily Cannabis Use
Those averages tell part of the story. A subset of six participants had much larger jumps: systolic blood pressure climbed from about 131 to nearly 147, and diastolic went from roughly 78 to 87. That is a swing of almost 23 points on the top number and over 12 on the bottom number.1PubMed Central. Increased Blood Pressure Following Abrupt Cessation of Daily Cannabis Use To put that in perspective, a jump from 131 to 147 takes someone from borderline-high blood pressure into stage-1 hypertension territory. If that person already had cardiovascular risk factors, the spike could be clinically meaningful.
The study involved daily users who stopped abruptly, which is exactly the scenario a person searching this question is likely in. This was not a case of casual weekend users experiencing mild discomfort. These were people whose bodies had adapted to a daily supply of THC, and the withdrawal response was measurable and consistent across participants.
Why Cannabis Lowers Blood Pressure in the First Place
To understand why stopping raises blood pressure, it helps to know what cannabis does to your cardiovascular system while you are using it. Your body has its own built-in cannabinoid signaling system, the endocannabinoid system, which among many roles helps regulate blood vessel tone and heart function. THC plugs into that system and generally pushes it toward lower blood pressure and reduced heart workload.2PubMed Central. Blood pressure regulation by endocannabinoids and their receptors
This blood-pressure-lowering effect is well established in research on both natural and synthetic cannabinoids. The endocannabinoid system plays a broad role in cardiovascular regulation, with involvement in conditions ranging from low blood pressure during severe illness to blood pressure management in chronic hypertension.2PubMed Central. Blood pressure regulation by endocannabinoids and their receptors When you flood that system daily with THC, your body adjusts to operating with that extra downward push on blood pressure. Take the THC away, and the system overcorrects.
The Stress Hormone Connection
The blood pressure rebound during withdrawal is not just a passive “the brakes are off” phenomenon. Your body actively revs up stress signaling during cannabis withdrawal. Research tracking neurotransmitter levels in cannabis-dependent individuals over 28 days of abstinence found that epinephrine, one of the main stress hormones, increased significantly during the withdrawal period.3PubMed Central. Characterization of cannabis withdrawal symptoms and serum levels of neurotransmitters among cannabis-dependent smokers during sustained abstinence within a controlled residential environment Meanwhile, serotonin and dopamine levels dropped, which may contribute to the irritability and low mood that make withdrawal so unpleasant.
This pattern fits a broader picture seen across multiple substances. During withdrawal from chronic drug use, noradrenergic signaling (the part of the nervous system that controls your fight-or-flight response) tends to spike. This elevated norepinephrine activity is consistent enough across different substances that researchers have proposed it as a common thread linking withdrawal states from alcohol, nicotine, cannabis, and other drugs.4PubMed Central. Elevated Norepinephrine may be a Unifying Etiological Factor in the Abuse of a Broad Range of Substances: Alcohol, Nicotine, Marijuana, Heroin, Cocaine, and Caffeine Norepinephrine is a direct blood-pressure raiser. It tightens blood vessels and increases heart rate. If your body is pumping out more of it because it is adjusting to the sudden absence of cannabis, your blood pressure goes up as a straightforward consequence.
So two things are happening at once: the blood-pressure-lowering effect of THC on the endocannabinoid system disappears, and your stress hormones surge in the opposite direction. That double hit explains why the blood pressure increase during cannabis withdrawal can be more dramatic than you might expect from simply “not being high anymore.”
Where This Falls in the Withdrawal Timeline
Cannabis withdrawal follows a fairly predictable arc. Symptoms typically begin within a day or two after stopping and peak somewhere between days two and six. Most symptoms settle down within a few weeks, though some heavy users report lingering effects for three weeks or longer.5PubMed Central. Clinical Management of Withdrawal The most commonly reported symptoms are psychological: anxiety, irritability, anger, sleep disruption, depressed mood, and loss of appetite. Physical symptoms like chills, headaches, sweating, and stomach pain are less frequent but do occur.5PubMed Central. Clinical Management of Withdrawal
Blood pressure changes do not usually make it onto standard withdrawal symptom lists. That is partly because they are silent: you cannot feel your blood pressure the way you can feel anxiety or insomnia. Unless someone is monitoring their readings during withdrawal, they would have no idea their numbers had climbed. The study that documented these increases captured them precisely because participants were being monitored in a research setting. In ordinary life, the spike happens and resolves without anyone noticing, unless it causes symptoms like headache or dizziness, which might get chalked up to other withdrawal effects.
The research on neurotransmitter changes tracked participants out to 28 days, finding that the epinephrine increase persisted throughout that period.3PubMed Central. Characterization of cannabis withdrawal symptoms and serum levels of neurotransmitters among cannabis-dependent smokers during sustained abstinence within a controlled residential environment Whether blood pressure stays elevated that long in most people is less clear, because few studies have tracked it over such an extended window. What is reasonable to expect is that the worst of the blood pressure spike aligns with the broader withdrawal peak in the first week, with a gradual return toward baseline as the body recalibrates.
Not Everyone Gets the Same Spike
One of the most important findings in the key study on this topic is how unevenly the blood pressure increase was distributed. The overall group averaged a rise of about 10 points systolic, which is notable but not necessarily alarming for a healthy person. But a subset of participants saw much larger jumps, approaching 23 points systolic.1PubMed Central. Increased Blood Pressure Following Abrupt Cessation of Daily Cannabis Use The researchers noted that this kind of increase could be clinically significant, particularly for people who already have elevated blood pressure or heart disease risk factors.
What separated the big responders from the moderate responders is not entirely clear from the existing research. The study sample was relatively small, which makes it hard to identify reliable predictors. Still, some reasonable inferences exist. Heavier, more frequent use likely leads to greater physiological adaptation and therefore a bigger rebound. People whose baseline blood pressure is already in the borderline range have less margin before a withdrawal-related spike pushes them into hypertension. Age, family history, and co-existing conditions like diabetes or kidney disease all influence how well the cardiovascular system handles sudden changes.
If you already take blood pressure medication and use cannabis daily, the interaction becomes complicated. Cannabis may have been masking a higher underlying blood pressure, or your medication dose may have been calibrated while cannabis was keeping your numbers partially suppressed. Stopping cannabis could unmask a blood pressure that your current medication dose is not quite controlling. This is not a reason to keep using cannabis, but it is a reason to let your doctor know what is happening if you decide to quit.
Why This Gets Missed in Clinical Settings
Cannabis withdrawal has historically been underrecognized in medicine. For decades, the conventional wisdom was that cannabis was not physically addictive and that withdrawal was either nonexistent or trivially mild. That view has shifted as research accumulated showing that a genuine withdrawal syndrome exists, but awareness still lags among many practitioners. Blood pressure effects in particular are easy to overlook because they are not part of the formal diagnostic criteria for cannabis withdrawal syndrome, which focuses on mood changes, sleep problems, appetite changes, and restlessness.
A person who quits cannabis, develops elevated blood pressure during the withdrawal window, and visits their doctor might get diagnosed with new-onset hypertension and started on medication. If neither the patient nor the doctor connects the timing to cannabis cessation, the diagnosis sticks. There is no way to know how often this happens, but the blood pressure study’s authors flagged exactly this concern: that clinically significant blood pressure increases following abrupt cannabis cessation may go unrecognized.1PubMed Central. Increased Blood Pressure Following Abrupt Cessation of Daily Cannabis Use
The practical message is straightforward. If you are quitting daily cannabis use and your blood pressure readings come back higher than expected in the first few weeks, consider whether the timing lines up with your cessation before assuming the elevated numbers represent your new normal. Rechecking after a month or two of sustained abstinence gives a much clearer picture of where your cardiovascular health actually stands.
Medications Researchers Have Tested
Because the norepinephrine surge appears to be a key driver of cannabis withdrawal discomfort, including blood pressure effects, researchers have tested medications that dial down noradrenergic activity. One approach uses drugs called alpha-2 adrenergic agonists, which work by telling the brain to release less norepinephrine. These drugs are already used to treat high blood pressure in other contexts.
Lofexidine, an alpha-2 agonist, was tested in a controlled study of cannabis withdrawal and relapse. The rationale was that by dampening the stress-response overshoot, it might ease withdrawal symptoms and reduce the urge to start using again.6PubMed Central. Effects of THC and lofexidine in a human laboratory model of marijuana withdrawal and relapse It showed some benefit for sleep disruption during withdrawal, but side effects like fatigue and low blood pressure limited its practicality as a treatment people could easily use day to day.7PubMed Central. Guanfacine decreases symptoms of cannabis withdrawal in daily cannabis smokers
Guanfacine, a related medication that is already FDA-approved for ADHD and high blood pressure, was tested as a potentially better-tolerated alternative. Researchers evaluated whether a daily bedtime dose could reduce cannabis withdrawal symptoms without the problematic side effects seen with lofexidine.7PubMed Central. Guanfacine decreases symptoms of cannabis withdrawal in daily cannabis smokers The logic makes sense on paper: if norepinephrine overactivity is driving both the mood symptoms and the blood pressure spike, a drug that calms norepinephrine release should help with both. Other pharmacological approaches that have been explored for managing the acute cardiovascular effects of cannabis include beta-blockers and other heart-focused medications.8PubMed Central. Pharmacological interventions in the treatment of the acute effects of cannabis: a systematic review of literature
None of these treatments are established standard practice for cannabis withdrawal. The research is still in early stages, and most people who quit cannabis get through withdrawal without any medication. But for someone with pre-existing hypertension or cardiovascular disease who is concerned about blood pressure spikes during withdrawal, knowing that these options are being studied is useful context for a conversation with their doctor.
Cannabis Use and Blood Pressure Over the Long Term
The withdrawal blood pressure spike is a short-term phenomenon, but it sits within a more complicated long-term picture. While THC tends to lower blood pressure acutely, chronic cannabis use may not be straightforwardly protective for cardiovascular health. The endocannabinoid system’s role in blood pressure regulation is complex, involving direct effects on the heart and blood vessels through multiple pathways.2PubMed Central. Blood pressure regulation by endocannabinoids and their receptors Depending on the context, cannabinoids can have different and sometimes opposing effects on cardiovascular function.
What this means for a daily user is that cannabis may have been keeping their blood pressure readings artificially low, creating a misleading picture of their cardiovascular baseline. The withdrawal spike, while genuinely caused by cessation, might be revealing a truer resting blood pressure that was being masked by daily use. For some people, the “elevated” readings during withdrawal might stabilize at a level that is still higher than what they saw while using but that represents their actual physiology without cannabis in the picture.
This distinction matters for how you interpret post-cessation blood pressure numbers. If your readings settle into a higher range after the acute withdrawal period has passed, that is worth investigating on its own terms, not as a lingering withdrawal effect but as your genuine baseline that cannabis was suppressing.
Gradual Reduction Versus Cold Turkey
The study documenting the blood pressure spike specifically involved abrupt cessation of daily use.1PubMed Central. Increased Blood Pressure Following Abrupt Cessation of Daily Cannabis Use Whether a gradual taper produces a smaller blood pressure rebound has not been rigorously tested. From a physiological standpoint, it is plausible that a slow reduction would give the endocannabinoid system and the stress-response pathways time to readjust incrementally, rather than being forced to recalibrate all at once. That logic is borrowed from how tapers work for other substances where abrupt withdrawal causes cardiovascular strain.
For a healthy person with no cardiovascular risk factors, quitting cold turkey and riding through a temporary blood pressure bump is unlikely to cause harm. The readings may climb for a week or two and then come back down, and the person may never notice. For someone with existing hypertension, heart disease, or significant risk factors, a more cautious approach seems reasonable, both in terms of potentially tapering and in terms of monitoring blood pressure more closely during the transition. There is no formal guideline for this because the evidence base is thin, but the general principle of avoiding sudden physiological shocks in people with vulnerable cardiovascular systems applies here as much as anywhere.
If you are planning to quit daily cannabis use and you have concerns about your blood pressure, the simplest step is to buy an inexpensive home blood pressure monitor and check your readings a few times per day during the first two weeks of abstinence. That gives you concrete data to share with a doctor if the numbers climb into a range that concerns you, and it lets you track the expected decline as your body adjusts to functioning without daily THC.