Cannabis and Lisinopril (Zestril)
Generic: lisinopril
Brand names: Zestril, Prinivil
Important Medical Disclaimer
This information is for educational purposes only and does not constitute medical advice. Do not start, stop, or modify your use of Lisinopril or cannabis without consulting your doctor or pharmacist. If you experience adverse effects, seek immediate medical attention. Individual responses to drug combinations vary significantly.
Overview
Lisinopril (Zestril, Prinivil) is an ACE inhibitor prescribed for hypertension, heart failure, and post-myocardial infarction management. The interaction with cannabis is rated LOW RISK because lisinopril has no hepatic metabolism (it is excreted unchanged by the kidneys) and therefore no CYP450-mediated pharmacokinetic interaction with cannabinoids. The primary concern is a mild pharmacodynamic interaction: both cannabis and lisinopril can lower blood pressure, and their combination may cause additive hypotension. THC has complex cardiovascular effects, initially causing tachycardia and a mild increase in blood pressure followed by a decrease in blood pressure, particularly upon standing (orthostatic hypotension). When combined with lisinopril's blood pressure-lowering effect, some patients may experience dizziness, lightheadedness, or fainting, particularly upon standing or with sudden position changes. This effect is generally more pronounced in patients who are new to either medication or cannabis, elderly patients, or those who are dehydrated. Despite the low overall risk rating, patients with unstable blood pressure, heart failure, or a history of syncope should exercise appropriate caution. This information is for educational purposes only. Consult your healthcare provider.
How They Interact
Lisinopril inhibits angiotensin-converting enzyme, preventing the conversion of angiotensin I to angiotensin II, resulting in vasodilation and reduced aldosterone secretion. It is not metabolized hepatically and is excreted unchanged in the urine, making it free from CYP450-mediated drug interactions. THC activates CB1 receptors in the vasculature, producing acute vasodilation and, in some cases, orthostatic hypotension. The combination of ACE-mediated vasodilation and cannabinoid-mediated vasodilation can produce additive blood pressure reduction. CBD may also contribute to hypotension through its effects on vascular smooth muscle relaxation and reduced peripheral resistance. The endocannabinoid system plays a role in blood pressure regulation, and exogenous cannabinoids can enhance the hypotensive effects of antihypertensive medications through these vascular mechanisms.
Cannabinoid-Specific Interactions
| Cannabinoid | Interaction with Lisinopril |
|---|---|
| CBD | CBD does not affect lisinopril metabolism because lisinopril has no hepatic clearance. However, CBD has mild hypotensive properties through effects on vascular smooth muscle, which may add to lisinopril's blood pressure-lowering effect. The clinical significance is generally mild but can be relevant in patients with already-low blood pressure. |
| THC | THC causes acute cardiovascular changes including tachycardia, initial blood pressure elevation, and subsequent orthostatic hypotension. When combined with lisinopril, the orthostatic hypotension may be more pronounced, leading to dizziness and fall risk, especially upon standing quickly. |
| CBN | CBN has mild sedative and potential hypotensive effects. While these are unlikely to cause significant clinical issues with lisinopril, patients should be aware of additive dizziness and lightheadedness, particularly during initial co-use. |
Symptoms to Watch For
- ⚠Dizziness or lightheadedness, especially upon standing
- ⚠Feeling faint or actual fainting (syncope)
- ⚠Increased heart rate (compensatory tachycardia)
Recommendations
- 1Rise slowly from sitting or lying positions to minimize orthostatic hypotension when using both substances.
- 2Stay well hydrated, as dehydration exacerbates the blood pressure-lowering effects of both substances.
- 3Monitor your blood pressure at home if you use cannabis regularly while taking lisinopril.
- 4Inform your physician about cannabis use, especially if you experience frequent dizziness or near-fainting episodes.
Research Summary
Lisinopril's lack of hepatic metabolism makes it one of the lower-risk antihypertensive medications for pharmacokinetic interactions with cannabinoids. The pharmacodynamic interaction — additive hypotension — is mild and well-predicted based on the known cardiovascular effects of both cannabinoids and ACE inhibitors. A 2017 randomized controlled trial demonstrated that a single dose of CBD (600 mg) reduced resting blood pressure in healthy volunteers, supporting the biological plausibility of additive hypotension. Observational studies of medical cannabis patients on antihypertensive medications have not identified significant adverse cardiovascular events attributable to the combination, though data are limited and confounded by heterogeneous cannabis products and doses. Current guidelines do not contraindicate cannabis use with ACE inhibitors but recommend monitoring blood pressure. This information is for educational purposes only. Consult your healthcare provider.
Frequently Asked Questions
Is it safe to use cannabis while taking lisinopril?
The combination is considered low risk compared to many other drug-cannabis interactions. Lisinopril has no liver metabolism, so CBD won't affect its blood levels. The main concern is additive blood pressure lowering, which can cause dizziness. Most patients tolerate the combination well, but monitor for lightheadedness and discuss with your doctor.
Can marijuana affect my blood pressure medication?
Cannabis can add to the blood pressure-lowering effects of lisinopril, potentially causing dizziness or lightheadedness. THC in particular can cause orthostatic hypotension (blood pressure drop when standing). This is usually mild but can be significant in elderly patients or those with already-low blood pressure.
Should I take my blood pressure more often if I use cannabis?
If you use cannabis regularly while on lisinopril, home blood pressure monitoring is a good idea. Check your blood pressure at different times of day, including after cannabis use, to understand how the combination affects you. Share these readings with your doctor.