A mixed-methods study from southern Thailand found that most patients with diabetes and hypertension who use cannabis hold positive views of its health benefits, but only about one in three are aware that cannabis can interact with their prescription medications. The finding highlights an urgent counseling gap in primary care settings, regardless of whether cannabis itself proves therapeutic for these conditions.

As cannabis legalization advances across diverse regulatory contexts worldwide, primary care clinicians face a growing challenge: patients with chronic diseases like diabetes and hypertension are integrating cannabis into their self-management routines, often without disclosing use to their providers and almost always without understanding the pharmacological risks. In countries that have recently legalized cannabis, the mismatch between patient enthusiasm and patient knowledge about drug interactions represents a preventable safety hazard. This study from southern Thailand surfaces precisely that gap and makes the case that clinical systems need to respond with screening and counseling, not just surveillance.

Following Thailand’s 2022 cannabis regulatory revision, which effectively decriminalized cannabis and opened the door to broad commercial availability, patients with chronic diseases such as diabetes and hypertension began incorporating cannabis products into their self-management routines. This study used an exploratory-sequential mixed-methods design to understand how and why these patients use cannabis, what they believe about it, and what they know about its risks. The qualitative phase (11 in-depth interviews with patients and ancillary informants) identified four themes: cannabis as a health opportunity, cannabis as a potential health threat, cannabis as complementary medicine, and the role of social influence in shaping use patterns. These themes informed a cross-sectional survey administered to 124 cannabis-using patients across four levels of government NCD clinics in Songkhla Province.

The survey found that cannabis tea was the most common consumption form, used daily by most participants as a complement to, rather than replacement for, conventional medications. Roughly 68% of respondents viewed cannabis as a quality-of-life enhancer, and approximately 73% believed it acted faster than conventional medicines. Critically, only 34.7% of participants were aware that cannabis could interact with their concurrent prescription medications. No clinical outcome data (blood pressure readings, glycemic control markers, adverse events) were collected, so the actual health impact of cannabis use in this population remains unknown. The authors appropriately conclude that drug-interaction counseling and routine cannabis screening should be integrated into NCD clinic workflows, and that prospective studies with clinical endpoints are needed.

The Two-Thirds Problem: Most Cannabis-Using Chronic Disease Patients Don’t Know About Drug Interactions

In southern Thailand, where cannabis has been woven into traditional medicine recipes for centuries, patients with diabetes and high blood pressure are now legally brewing it into their morning tea, and two out of three have no idea it might be interfering with the prescription medications they’re already taking. That single statistic is the heart of this paper, and it matters more than the study’s other findings because it identifies a concrete, fixable safety problem. The study itself is modest in scope: 11 qualitative interviews followed by a 124-person survey of self-identified cannabis users at chronic disease clinics. It cannot tell us whether cannabis helps or harms diabetes or hypertension. What it does accomplish, and this is genuinely valuable, is to document a knowledge gap that clinicians can address today. The positive perceptions patients reported are real but should not be confused with evidence of efficacy. Asking patients whether they feel a medication is helping them, without measuring their blood pressure before and after, tells us about hope, not about the drug. Still, the fact that patients approach cannabis with optimism rather than skepticism is itself clinically useful: it tells me, as a physician, that the therapeutic relationship has an opening. Patients are willing to talk about cannabis use. They see it as part of their wellness. That willingness is an asset for clinical counseling, not a problem to suppress.

The methodological limitation I would flag most prominently is the recruitment strategy. By studying only patients who voluntarily disclosed cannabis use at their clinic visits, the authors are essentially studying the eating habits of a community by only interviewing people who raised their hands at a food fair. You learn a lot about food enthusiasts, but nothing about how the rest of the town actually eats. The patients who do not disclose cannabis use, whether from stigma, uncertainty, or simple omission, may have very different risk profiles and knowledge levels. This means the 34.7% awareness figure could be an overestimate (disclosers may be more health-literate) or an underestimate (non-disclosers may never have encountered any drug-interaction information at all). Without knowing the true denominator of cannabis users in these clinics, we cannot be certain of the number. But the direction of the finding is clear enough to act on. No reasonable clinician would wait for a randomized trial before beginning to ask their chronic disease patients about cannabis use and counseling them about CYP450 interactions with antihypertensives, oral hypoglycemics, and statins.

To a patient, I would say: I’m glad you told me you’re using cannabis alongside your medications, and the most important thing we need to discuss is how it might affect the way your body processes those prescriptions. To a colleague, I would say: this study does not tell us whether cannabis is helping or hurting these conditions, but the two-thirds who are unaware of interactions represent a patient safety problem we can address right now with routine screening and counseling. To a policymaker, I would say: you have created a context where patients with chronic diseases are using cannabis as medicine, often without their doctors knowing and almost always without understanding the pharmacological risks, and that demands investment in clinician training and patient education materials, not just market regulation. When a population long familiar with a plant suddenly gains legal access to it, they will use it with hope and without systematic safety knowledge, and the healthcare system needs to be ready with counseling, not just surveillance.

This study sits at the very beginning of the research arc for cannabis use among chronic disease patients in post-legalization Southeast Asia. It is hypothesis-generating, not hypothesis-testing. There are no controlled comparisons, no longitudinal follow-up, and no objective clinical endpoints. Its contribution is to characterize a patient population that exists in real clinical practice but has been largely invisible to formal research in this region. For clinicians working in newly legalized environments, the most important signal is not what patients believe about cannabis but what they do not know about its pharmacological interactions with drugs they are already taking.

Cannabis is metabolized primarily via the CYP3A4 and CYP2C9 pathways, and both THC and CBD can inhibit or induce these enzymes in ways that alter the metabolism of antihypertensives (particularly calcium channel blockers), oral hypoglycemics (including metformin and sulfonylureas), statins, and anticoagulants. The clinical significance of these interactions varies by dose, formulation, and individual patient pharmacogenomics, but the theoretical risk is well established. In a population where 90.3% carry a hypertension diagnosis and most are on multiple medications, ignorance of these interactions is not a theoretical concern. The single most actionable recommendation from this study is to implement routine, nonjudgmental cannabis use screening at every chronic disease clinic visit, paired with brief, specific counseling about the interaction risks most relevant to each patient’s medication list.

This is an exploratory-sequential mixed-methods study combining descriptive qualitative interviews with a cross-sectional quantitative survey. In the evidence hierarchy, it occupies the lower tiers: it is descriptive and observational, with no comparison group and no experimental manipulation. The single most important constraint on inference is that no clinical outcomes were measured, so the study can characterize what patients think and do but cannot determine whether cannabis use actually helps, harms, or has no effect on their chronic disease control.

This study extends a small but growing body of descriptive research on cannabis use in chronic disease populations following legalization. Earlier work from Thailand by Assanangkornchai and colleagues documented the initial wave of cannabis use for medical purposes after the 2019 partial legalization, and this study advances that line of inquiry by focusing specifically on chronic disease patients and their drug-interaction knowledge. Internationally, studies such as Collister et al. (2022) on cannabis use in chronic kidney disease and Vidot, Lerner, and Gonzalez (2017) on cannabis in HIV patients have similarly documented high rates of use alongside low rates of provider communication, reinforcing the pattern this study identifies. What distinguishes the present work is its focus on a non-Western, newly legalized context and its use of a mixed-methods design that allows patient voices to inform the quantitative instruments, a methodological strength that most prior studies lacked.

The most consequential analytic choice in this study was the decision to recruit only voluntarily disclosing cannabis users rather than screening all NCD clinic patients for cannabis use and then comparing users with non-users. Had the researchers administered a universal screening instrument to all clinic attendees, they would have captured non-disclosing users and been able to calculate a true prevalence of cannabis use, compare drug-interaction awareness between disclosers and non-disclosers, and assess whether cannabis-using patients differed from non-users on clinical parameters. This alternative approach would have substantially strengthened the study’s ability to generalize its findings and might have revealed a larger or smaller drug-interaction awareness gap than the 34.7% figure observed in this self-selected sample.

The most likely and most dangerous misreading of this study is to interpret the high prevalence of positive patient beliefs about cannabis as evidence that cannabis is therapeutically effective for diabetes or hypertension. This is a category error: patient perceptions are data about beliefs, not data about pharmacological efficacy. No clinical outcomes (blood pressure control, glycemic markers, adverse events) were measured in this study. A related misreading is to conclude that cannabis is “safe” for chronic disease patients because most users reported positive experiences. The study’s own most important finding, the drug-interaction awareness gap, directly undercuts any such conclusion by revealing that the majority of users are not even aware of the pharmacological risks they are incurring.

This study contributes the first systematic description of cannabis use behaviors, beliefs, and knowledge gaps among chronic disease patients in post-legalization southern Thailand. It does not establish whether cannabis is beneficial or harmful for diabetes or hypertension. Its most durable and actionable finding is the low rate of drug-interaction awareness (34.7%) among cannabis-using patients on prescription medications, a gap that primary care clinicians can begin to address now through routine screening and targeted counseling, without waiting for further evidence.

Does this study prove that cannabis helps with diabetes or high blood pressure?

No. The study did not measure any clinical outcomes like blood sugar levels or blood pressure readings. It only documented what patients believe and how they use cannabis. Many patients reported feeling that cannabis helped them, but feelings of benefit are not the same as measured health improvement. Controlled clinical trials would be needed to answer the question of whether cannabis actually improves chronic disease outcomes.

Should I be worried about cannabis interacting with my blood pressure or diabetes medications?

Yes, this is a legitimate concern. Cannabis is processed in the body by some of the same enzyme systems that break down many common prescription medications, including certain blood pressure drugs, diabetes medications, and cholesterol-lowering statins. This means cannabis can potentially change how much of those drugs stays active in your bloodstream, either increasing side effects or reducing effectiveness. If you use cannabis and take prescription medications, it is important to discuss this with your doctor so your medications can be monitored appropriately.

Is cannabis tea safer than other forms of cannabis?

This study found that cannabis tea was the most common form used by participants, but it did not compare the safety of different cannabis preparations. Cannabis tea may deliver lower and more variable doses of active compounds compared to concentrated extracts or smoked cannabis, but it can still contain enough THC and CBD to interact with prescription medications. The form of consumption does not eliminate the need for awareness of drug interactions.

Do these findings apply to patients outside Thailand?

The specific patterns of cannabis use, cultural attitudes, and regulatory context in this study are unique to southern Thailand. However, the core finding about low drug-interaction awareness is likely relevant wherever chronic disease patients use cannabis alongside prescription medications, which includes many post-legalization jurisdictions around the world. The principle that patients need clear information about cannabis-drug interactions is universal, even if the specific numbers may differ across populations.

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