Terrain support medications are existing, FDA-approved medications — originally developed for non-cancer indications — that demonstrate anti-cancer activity through epidemiological signals, mechanistic pathways, real-world data, or early clinical trials. The case for their use is not theoretical: many of the most clinically compelling cancer drugs of the coming decade may already exist, sitting in pharmacies for pennies per pill, waiting for the oncology community to recognize what the basic science has been showing for years. At Root Causes, terrain support medications are administered daily as part of the SEED core protocol — representing the sixth foundational therapy alongside IV Vitamin C, mistletoe, HBOT, ozone, and hyperthermia. They are organized into three tiers: a universal base protocol appropriate for most cancer patients, pathway-matched additions selected by tumor type and individual terrain, and an emerging watch list for rapidly evolving candidates. This document summarizes the evidence and rationale for each drug in the framework.
The most important framing for this entire white paper: the evidence gap in terrain support medications is structural, not scientific. Drug development in oncology is driven by patent economics. A new targeted therapy that costs $150,000 per year per patient generates the revenue that funds trials. Metformin, which costs $4 per month, does not. There is no commercial incentive to fund the large, well-powered RCTs that would establish definitive clinical evidence for off-patent drugs in cancer — even when the mechanistic and epidemiological signal is strong.
This means the evidence base for terrain support medications will never look like the evidence base for a newly approved targeted therapy — not because the drugs don't work, but because the system isn't designed to generate that evidence. The right framework for evaluating these drugs is: strong mechanistic rationale + epidemiological signal + safety profile + early clinical data, evaluated honestly. That is the framework applied in this document.
The ReDO (Repurposing Drugs in Oncology) Project, based in Belgium and published through ecancermedicalscience, is the most systematic published effort to evaluate terrain support medications for oncology. Their methodology and individual drug analyses are primary references throughout this white paper.
The conceptual architecture underlying the terrain support medication approach draws on the metabolic theory of cancer and the 'terrain' philosophy central to Root Causes' clinical model. Jane McClelland's framework, articulated in How to Starve Cancer, identifies three primary metabolic dependencies that cancer cells exploit, and that can be targeted simultaneously with available terrain support medications:
| Metabolic Target | Why Cancer Cells Depend on It | Key Drugs That Target It |
|---|---|---|
| Glucose / Glycolysis (Warburg Effect) | Cancer cells preferentially ferment glucose even in the presence of oxygen — generating energy inefficiently but rapidly, with metabolic byproducts that drive proliferation | Metformin, statins, aspirin, benzimidazoles, niclosamide |
| Glutamine | The second major cancer fuel — used for energy, biosynthesis, and redox balance; many cancers are highly glutamine-dependent | DON (emerging), niclosamide, metformin (indirect) |
| Fatty Acid Oxidation / Cholesterol | Cancer cells upregulate cholesterol synthesis (mevalonate pathway) and fatty acid metabolism to build membranes and signaling molecules | Statins (mevalonate), benzimidazoles, niclosamide |
| Immune Evasion / Stress Signaling | Cancer cells suppress immune surveillance and exploit sympathetic nervous system signaling to promote metastasis | Propranolol (beta-adrenergic), LDN (immune), cimetidine (NK/Treg), aspirin (COX-2/platelet) |
The multi-drug approach is intentional. Cancer's metabolic plasticity means that blocking a single pathway often results in compensatory upregulation of others. Simultaneously targeting multiple pathways reduces the likelihood of resistance and creates synergistic anti-tumor pressure — the same principle that transformed HIV treatment and continues to inform combination chemotherapy.
TIER 1 — Universal Base Protocol
Every SEED cancer patient. Multi-cancer evidence, favorable safety, addresses fundamental terrain drivers of cancer metabolism and immune evasion.
Metformin activates AMPK (AMP-activated protein kinase) — the master metabolic switch — which inhibits mTOR signaling, a primary driver of cancer cell proliferation and survival. It also inhibits Complex I of the mitochondrial electron transport chain, reducing cellular energy production and creating metabolic stress in cancer cells. Additional mechanisms include reduction of circulating insulin and IGF-1 (which both drive cancer proliferation), cancer stem cell suppression, autophagy modulation, and STAT3 inhibition.
EVIDENCE SUMMARY
Extensive epidemiological data: diabetic patients on metformin have significantly lower cancer incidence and cancer mortality compared to those on other diabetes medications — a signal observed across multiple cancer types. Clinical trials in pre-surgical endometrial cancer showed significant Ki67 reduction with metformin monotherapy. Central component of the Care Oncology COC protocol with published GBM data. Multiple ongoing clinical trials across cancer types. Evidence grade B: strong mechanistic and epidemiological foundation; clinical RCT evidence variable by cancer type.
CLINICAL NOTE
Variable clinical response likely reflects tumor metabolic heterogeneity. Patients with AMPK-activating mutations or highly glucose-dependent tumors may respond more robustly. Contraindicated in severe renal impairment (eGFR <30). GI side effects common at initiation — titrate slowly.
Statins inhibit HMG-CoA reductase — the rate-limiting enzyme in the mevalonate pathway — blocking cholesterol biosynthesis and, critically, prenylation of Ras and Rho GTPases required for cancer cell proliferation, survival, and metastasis. Cancer cells are highly dependent on the mevalonate pathway for membrane construction, signaling molecule production, and cell growth. Statins also induce cancer cell apoptosis, inhibit angiogenesis (VEGF suppression), reduce inflammation (CRP), and have immunomodulatory effects on the tumor microenvironment. Lipophilic statins (atorvastatin, simvastatin) penetrate tumor tissue more effectively than hydrophilic statins.
EVIDENCE SUMMARY
Strong epidemiological signal: statin use associated with reduced cancer mortality and improved outcomes across multiple cancer types in observational studies. The COC protocol uses atorvastatin 40–80 mg daily. The METRICS GBM study showed improved overall survival with the COC protocol including atorvastatin. ReDO project analysis supports further clinical investigation. Evidence grade B: strong mechanistic and epidemiological basis; RCT data limited.
CLINICAL NOTE
Atorvastatin preferred over simvastatin for its longer half-life (more consistent 24-hour coverage). Consider CoQ10 supplementation with statin use to offset mitochondrial effects. Monitor LFTs. Drug interactions with certain immunosuppressants and antifungals.
Doxycycline, a tetracycline-class antibiotic, inhibits mitochondrial biogenesis through inhibition of mitochondrial ribosome translation — directly targeting cancer stem cells (CSCs), which are highly dependent on oxidative phosphorylation (OXPHOS) for their energy metabolism. CSCs are the most treatment-resistant cancer cell population, responsible for recurrence and metastasis. Doxycycline also inhibits DNA-PK (sensitizing cancer cells to radiation), inhibits matrix metalloproteinases (reducing invasion and metastasis), and downregulates HIF-1α under certain conditions.
EVIDENCE SUMMARY
COC protocol component. Preclinical data demonstrates selective elimination of cancer stem cells while sparing differentiated cancer cells and normal cells. Clinical relevance enhanced when combined with metformin (which targets differentiated cancer cells metabolically) — the combination creates a two-pronged attack on both the tumor bulk and its stem cell reservoir. Evidence grade C: compelling mechanistic and preclinical data; clinical trial data in cancer as primary indication limited.
CLINICAL NOTE
COC protocol alternates mebendazole and doxycycline monthly rather than using both simultaneously. In SEED, clinical judgment guides which is more appropriate for a given patient. Photosensitivity is common — advise sun protection. Avoid dairy products and iron supplements within 2 hours of dosing.
Mebendazole — an antiparasitic benzimidazole — inhibits tubulin polymerization in cancer cells, disrupting mitotic spindle assembly and causing cell cycle arrest. It also suppresses VEGF-mediated angiogenesis, inhibits GLUT1 and GLUT4 glucose transporter expression (reducing glucose uptake), and activates p53-mediated apoptosis. The benzimidazole class (mebendazole, albendazole, fenbendazole) shares this mechanism with different bioavailability and pharmacokinetic profiles.
EVIDENCE SUMMARY
COC protocol cornerstone. Clinical Phase II data exists for mebendazole in recurrent GBM and colorectal cancer. Multiple case reports and observational data. Albendazole has Phase I/II clinical trial data in cancer and may be substituted based on clinical preference and availability. Evidence grade C.
CLINICAL NOTE
Mebendazole and albendazole are in the same benzimidazole class — clinically interchangeable in many contexts. Mebendazole has more integrative oncology clinical experience; albendazole has more formal Phase I/II trial data. Fat-soluble — absorption significantly increased when taken with a fatty meal. Monitor LFTs with prolonged use.
Aspirin (acetylsalicylic acid) has the strongest evidence base of any drug in this white paper. Its anti-cancer mechanisms are multiple: irreversible COX-2 inhibition reduces tumor-promoting prostaglandin synthesis and inflammatory signaling; anti-platelet activity disrupts platelet-mediated protection of circulating tumor cells (CTCs) in the bloodstream — one of the key mechanisms of metastatic seeding; NF-κB pathway suppression reduces cancer cell survival signaling; and aspirin affects DNA repair pathways, with particular relevance in colorectal and microsatellite-unstable cancers.
EVIDENCE SUMMARY
A systematic review and meta-analysis of 118 observational studies across 18 cancer types demonstrated consistent survival benefits with aspirin use. Aspirin use associated with lower breast cancer-specific death (HR 0.69), reduced colorectal cancer risk (20% reduction per 325mg/day increment), improved ovarian cancer outcomes, and reduced lung cancer mortality. Multiple positive signals from RCTs originally designed to assess cardiovascular outcomes. Evidence grade A/B — the single best-evidenced terrain support medication in the entire oncology space.
CLINICAL NOTE
Low-dose aspirin (75–325mg daily) provides most of the anti-cancer benefit with lower GI risk. Enteric-coated formulation recommended for GI-sensitive patients. Contraindicated in active peptic ulcer, severe renal/hepatic impairment, active bleeding. Combine with dipyridamole for enhanced anti-platelet and anti-metastatic effect. Monitor for GI bleeding.
The beta-adrenergic stress pathway is a clinically underappreciated driver of cancer progression. Epinephrine and norepinephrine — released chronically in cancer patients experiencing fear, anxiety, and pain — directly suppress NK cell activity, promote tumor angiogenesis via VEGF upregulation, enhance cancer cell invasion, and accelerate metastasis through multiple mechanisms. Propranolol, a non-selective beta-1 and beta-2 blocker, interrupts this pathway. Specific mechanisms include: inhibition of cancer cell proliferation and invasion; suppression of MMP-2 and VEGF; NK cell activity preservation; and direct T-cell differentiation effects via adrenergic receptor blockade.
EVIDENCE SUMMARY
Propranolol increases immune cell infiltration into the tumor bed, significantly reduces recurrence risk in breast cancer and melanoma, and potentiates the immune effects of pembrolizumab in melanoma. Combined with anti-COX-2 agents peri-operatively in three RCTs, propranolol minimizes surgical stress, improves tumor molecular markers, and reinforces anti-tumor immune response. Particularly compelling in the surgical/peri-operative setting where stress catecholamines spike. Evidence grade B.
CLINICAL NOTE
The stress pathway suppression argument is especially compelling for SEED patients — a cancer diagnosis with active/advanced disease is one of the highest-stress clinical scenarios imaginable. Contraindicated in bronchospastic pulmonary disease, decompensated heart failure, bradycardia, and certain arrhythmias. Monitor heart rate and blood pressure.
At standard doses (50mg), naltrexone is an opioid receptor blocker used for addiction. At low doses (1.5–4.5mg), taken at night, it creates a brief period of opioid receptor blockade that triggers a rebound upregulation of endogenous endorphins and enkephalins. The proposed oncological mechanism involves TLR4 (Toll-like Receptor 4) antagonism — reducing inflammatory cytokine signaling in the tumor microenvironment — and immune modulation through enhanced NK cell and T-cell activity.
EVIDENCE SUMMARY
LDN has a passionate clinical following and a growing case series in multiple sclerosis, fibromyalgia, Crohn's disease, and several cancer types. The oncology evidence is primarily case series and preclinical; no large RCTs exist. Mechanistic rationale is plausible but not definitively proven at clinical scale. Evidence grade C/D — included for completeness and because the safety profile is excellent and the anecdotal clinical signal is consistent enough to warrant inclusion, while acknowledging the evidence gap honestly.
CLINICAL NOTE
Excellent safety profile is the primary reason for inclusion — low-dose naltrexone has virtually no serious adverse effects and is extremely well-tolerated. Must be taken at night and must not be used in patients on opioid medications. Custom compounding required (not commercially available at low doses).
TIER 2 — Pathway-Matched Additions
Selected by tumor type, molecular profile, and individual terrain. Added to the Tier 1 base protocol based on clinical judgment and patient-specific factors.
Ivermectin — an antiparasitic agent with decades of human safety data — has emerged as one of the most mechanistically interesting terrain support medications. Key mechanisms include: PAK1 kinase inhibition (PAK1 drives tumor growth and progression in breast cancer, NF2, and other cancers); WNT/β-catenin pathway suppression (relevant in colorectal, breast, GBM, and many others); immunogenic cell death induction; SIN3A pathway modulation affecting gene expression; and potential synergy with immune checkpoint inhibitors. A 2024 peer-reviewed protocol combining ivermectin, mebendazole, and fenbendazole was formally published.
EVIDENCE SUMMARY
Growing preclinical evidence across multiple cancer types. Small clinical studies and case reports with promising signals. Phase I/II study at Cedars-Sinai Medical Center evaluating safety and efficacy in cancer. Evidence grade C — strong mechanistic foundation and growing clinical signal; large RCTs still needed.
CLINICAL NOTE
High-dose ivermectin for cancer is an active area of investigation — dosing regimens differ significantly from antiparasitic use and are still being defined. Clinical judgment required for dosing. Interactions with P-glycoprotein substrates. Do not use in patients with blood-brain barrier disruption at high doses.
Niclosamide — an anthelmintic approved since the 1960s — simultaneously targets multiple oncogenic signaling pathways: Wnt/β-catenin (cancer stem cell maintenance), STAT3 (immune evasion, cell survival), mTOR (proliferation), Notch (stemness), and NF-κB (inflammation, survival). This multi-pathway simultaneous targeting makes it one of the most mechanistically comprehensive agents in the terrain support medication space. Particularly relevant to cancer stem cells, which co-opt Wnt and Notch signaling for self-renewal.
EVIDENCE SUMMARY
Strong preclinical data across colorectal, prostate, breast, ovarian, and head and neck cancers. Clinical development has been limited by oral bioavailability challenges — new formulations including injectable and polymer matrix preparations are in active development. Evidence grade C — mechanistically compelling; clinical evidence limited by formulation challenges.
CLINICAL NOTE
Oral bioavailability of standard tablet formulation is poor — absorption is highly variable. Enhanced formulations (SUBA-niclosamide, nanoparticle delivery) are in development and may significantly improve clinical utility. Best candidates: colorectal cancer (strong Wnt signal), prostate cancer (STAT3), and cancers with high cancer stem cell burden.
Itraconazole — a widely used triazole antifungal — was identified through drug screening as a potent inhibitor of the Hedgehog (Hh) signaling pathway at clinically achievable concentrations. It acts on Smoothened (SMO) via a mechanism distinct from other Hh antagonists, preventing SMO ciliary accumulation. Additional mechanisms include potent anti-angiogenic activity, mTOR pathway inhibition, and induction of autophagic growth arrest. The Hedgehog pathway is particularly important in basal cell carcinoma, medulloblastoma, and a subset of lung, prostate, and pancreatic cancers.
EVIDENCE SUMMARY
Clinical trials have demonstrated benefit in prostate cancer (reduced PSA, tumor regression), non-small cell lung cancer, and basal cell carcinoma. Additional reports of activity in leukemia, ovarian, breast, and pancreatic cancers. Evidence grade C — potent anti-angiogenic and Hedgehog inhibition at clinical concentrations; clinical trial results positive in specific cancer types.
CLINICAL NOTE
At Root Causes, itraconazole is particularly valuable when chronic fungal infection is suspected or confirmed — addressing a terrain issue (occult fungal burden) while simultaneously providing anti-cancer pathway effects. CYP3A4 interactions require medication review. Monitor LFTs. Drug interactions with statins may increase statin exposure.
HCQ accumulates in lysosomes and raises their pH, blocking the autophagic flux that cancer cells — particularly under metabolic stress — use to recycle cellular components and survive. This is most therapeutically relevant when HCQ is combined with agents that induce metabolic stress (metformin, benzimidazoles) or nutrient deprivation, forcing cancer cells into autophagy-dependent survival mode and then blocking that escape route. HCQ also has immunomodulatory properties and may affect the tumor immune microenvironment.
EVIDENCE SUMMARY
Mixed clinical trial results as monotherapy. Most compelling data in combination with metabolic stressors. A key principle: HCQ's benefit depends on creating the metabolic context in which autophagy is an active cancer survival mechanism — it works best as part of a metabolic combination. Evidence grade C — context-dependent; combinations with metformin or glycolysis inhibitors are the rational clinical use case.
CLINICAL NOTE
Annual ophthalmology exam recommended with long-term HCQ use (retinopathy risk at cumulative doses). Dose-dependent risk — standard oncology research doses are often higher than the anti-malarial doses associated with retinopathy. Best used as a combination partner, not standalone therapy.
Cimetidine — a histamine H2-receptor antagonist — has anti-cancer effects extending well beyond acid suppression. Key mechanisms include: blocking histamine-driven cancer cell proliferation (H2 receptors expressed on many cancer cells); inhibiting E-selectin expression on endothelium, which reduces circulating tumor cell adhesion and metastatic seeding; modulating regulatory T cells, dendritic cells, and NK cell activity in the tumor microenvironment; and anti-angiogenic effects. The E-selectin mechanism is particularly relevant for preventing liver and lymph node metastasis.
EVIDENCE SUMMARY
Demonstrated positive effects in colorectal cancer, gastric cancer, melanoma, and renal cell carcinoma. A Cochrane review assessed H2 receptor antagonists as adjuvant treatment for resected colorectal cancer. Particularly compelling in the peri-operative period — E-selectin is upregulated during surgery, and cimetidine blocks this metastatic vulnerability window. Evidence grade B for GI cancers; C for other tumor types.
CLINICAL NOTE
CYP3A4 inhibitor — review drug interactions carefully. Most compelling in GI cancers (colorectal, gastric) and as peri-operative protection. Excellent safety profile. May be added to aspirin + dipyridamole as part of a comprehensive anti-metastatic combination.
Dipyridamole inhibits platelet aggregation and adenosine uptake, creating an immunostimulatory microenvironment through elevated extracellular adenosine. The anti-platelet mechanism synergizes with aspirin to more completely disrupt platelet-mediated CTC protection — cancer cells exploit platelet cloaking to evade NK cell surveillance in the bloodstream. Dipyridamole also has direct anti-proliferative effects in some cell lines and may enhance the anti-cancer effects of certain chemotherapy agents.
EVIDENCE SUMMARY
Less direct anti-cancer evidence than aspirin, but the mechanistic synergy with aspirin is compelling. Observational data supports the aspirin + dipyridamole combination for cardiovascular disease, with emerging oncological rationale for the pairing. Evidence grade C as standalone; B when considered as part of aspirin combination for anti-metastatic effect.
CLINICAL NOTE
Best used as an aspirin pairing for comprehensive anti-platelet and anti-CTC coverage. Extended-release dipyridamole (200mg) is the most studied formulation. Headache is the most common side effect, often transient. Contraindicated in severe coronary artery disease and in patients with myasthenia gravis.
Fenbendazole — a veterinary anthelmintic in the same benzimidazole class as mebendazole — disrupts tubulin polymerization, activates p53-mediated apoptosis, and suppresses GLUT4 glucose transporter expression. The Joe Tippens case (stage IV small cell lung cancer attributed to resolution after fenbendazole use) popularized it, but the preclinical data is independent and legitimate. A 2024 peer-reviewed protocol combining ivermectin, mebendazole, and fenbendazole was published.
EVIDENCE SUMMARY
Strong preclinical data. Limited published human clinical evidence — this is the key honest constraint distinguishing it from mebendazole and albendazole, which have formal Phase I/II trial data. Evidence grade C — included because the preclinical signal is real and the drug is widely used by patients independently, warranting clinical guidance.
CLINICAL NOTE
No approved human formulation — patients typically use veterinary products (Safe-Guard or Panacur), which carries quality control uncertainties. Clinical oversight is particularly important for this drug. Best positioned as an adjunct to mebendazole or albendazole rather than a replacement, given the stronger clinical evidence base of the latter two.
Metronidazole, as a nitroimidazole, selectively accumulates in hypoxic tissue — where it is reduced by cellular metabolism to reactive intermediates that cause DNA strand breaks. Hypoxic tumor cells are the primary target of radiosensitization. This mechanism is most relevant for patients receiving concurrent radiation therapy.
EVIDENCE SUMMARY
Historical clinical interest as a radiosensitizer from the 1970s–1980s. Evidence limited and largely superceded by other approaches. Most clinically compelling in the context of hypoxic tumor management — particularly as a complement to the HBOT and ozone hypoxia-reversal approach in SEED. Evidence grade D — older and limited clinical evidence; included primarily in the context of concurrent radiation.
CLINICAL NOTE
Most relevant for patients undergoing concurrent radiotherapy with known hypoxic tumor regions. The hypoxia-targeting mechanism aligns with SEED's broader anti-hypoxia approach (HBOT + ozone) — metronidazole adds direct cytotoxic pressure on hypoxic cells while HBOT/ozone improve oxygenation. Not a universal addition.
TIER 3 — Emerging / Investigational Watch List
Strong mechanistic rationale and growing scientific interest. Not yet ready for standard protocol inclusion — watch this space.
DON is a glutamine antagonist — it irreversibly inhibits glutamine-consuming enzymes, blocking the glutamine pathway that many cancers rely on as their second major fuel source after glucose. Originally investigated in the 1950s–80s, it was abandoned due to significant GI toxicity at the doses required. Now being reformulated as prodrugs (JHU-083, DRP-104) designed to release active DON preferentially in the tumor microenvironment, dramatically improving the therapeutic index. The glutamine pathway is Jane McClelland's third major cancer fuel target — and DON is the most direct pharmaceutical way to block it.
EVIDENCE SUMMARY
JHU and other major research centers have renewed active interest. Preclinical data shows remarkable efficacy in multiple tumor types including pancreatic cancer, colorectal cancer, and glioblastoma. Phase I trials of prodrug formulations are underway. Evidence grade C (emerging) — the science is compelling; clinical availability is the constraint. One to watch closely as prodrug trials report results.
CLINICAL NOTE
Not currently commercially available — prodrug formulations in Phase I trials. Patients cannot access DON through standard channels. Include in monitoring list; revisit for protocol inclusion as Phase I/II results emerge. When available, would pair naturally with metformin for comprehensive glycolysis + glutamine pathway blockade.
The foundation of the terrain support medication approach is simultaneous multi-pathway targeting. Cancer is not a single-pathway disease — it is a disease of metabolic and signaling dysregulation across multiple interdependent systems. Single-agent targeting, even with mechanistically sound drugs, is vulnerable to compensatory pathway upregulation. The combination approach, inspired by the COC protocol and McClelland's framework, is designed to close these escape routes.
The COC protocol (metformin + atorvastatin + doxycycline + mebendazole, with doxycycline and mebendazole alternated monthly) represents the most clinically tested terrain support medication combination in integrative oncology. The METRICS study — 95 GBM patients receiving COC protocol alongside standard of care — reported median overall survival of 26.3 months and 2-year survival of 55.8%, compared to 14.8 months and 28.7% with standard of care alone in matched Public Health England data. This is not RCT-level evidence, but the magnitude of difference in one of oncology's most treatment-resistant cancers is clinically meaningful. The Root Causes Tier 1 base protocol extends the COC foundation by adding aspirin, propranolol, and LDN — addressing anti-metastatic, stress-pathway, and immune terrain dimensions not covered by the original four drugs.
Jane McClelland's framework in How to Starve Cancer conceptualizes treatment as a metabolic blockade at three levels simultaneously: glucose/glycolysis (metformin, aspirin, benzimidazoles), glutamine (DON when available; niclosamide as partial substitute), and fatty acid/cholesterol (statins, benzimidazoles). The Tier 1 protocol accomplishes the first and third blocks at minimum. As Tier 2 drugs are added — particularly niclosamide — the glutamine pathway becomes increasingly targeted. The addition of DON (Tier 3) would complete the triple-block when it becomes clinically available.
Individual drug safety profiles are noted in each drug card above. The following considerations apply to the multi-drug combination approach:
Drug interactions — the combination of statins and itraconazole (both CYP3A4 substrates) significantly increases statin exposure — monitor for myopathy; dose adjustment may be required
Liver function monitoring — metformin, statins, doxycycline, mebendazole/albendazole, and itraconazole all carry hepatic monitoring considerations; baseline LFTs and periodic monitoring are recommended for patients on multiple agents
Renal function — metformin is contraindicated in significant renal impairment (eGFR <30); aspirin requires caution with renal compromise
GI tolerance — metformin, doxycycline, aspirin, mebendazole, and cimetidine all have GI side effects; stagger timing, use food where appropriate, and titrate doses gradually
Opioid use — LDN is absolutely contraindicated in patients on opioid analgesics; opioid use is common in advanced cancer patients — screen before initiating LDN
Cardiac contraindications — propranolol is contraindicated in bronchospastic disease, decompensated heart failure, and significant bradycardia; beta-blockers should not be discontinued abruptly
Ophthalmological monitoring — HCQ requires annual ophthalmology screening; cumulative dose tracking is necessary
| Drug | Primary Mechanism | Best Cancer Types / Context | Grade | Tier |
|---|---|---|---|---|
| Metformin | AMPK / mTOR / insulin | Broad; hormone-sensitive, metabolic, GBM | B | 1 |
| Atorvastatin | Mevalonate / Ras/Rho GTPase | Broad; hormone-sensitive, GI, lung | B | 1 |
| Doxycycline | Mitochondrial / CSC targeting | Broad; high CSC burden tumors | C | 1 |
| Mebendazole | Tubulin / VEGF / GLUT | GBM, colorectal, broad | C | 1 |
| Aspirin | COX-2 / anti-platelet / CTC | Broad; especially GI, breast, ovarian | A | 1 |
| Propranolol | Beta-adrenergic / anti-metastatic | Broad; especially peri-surgical, breast, melanoma | B | 1 |
| LDN | TLR4 / endorphin / immune | Broad; low-evidence but very safe | D | 1 |
| Ivermectin | PAK1 / WNT / ICD | Breast, GBM, broad | C | 2 |
| Niclosamide | Wnt/STAT3/mTOR/Notch/CSC | Colorectal, prostate, breast | C | 2 |
| Itraconazole | Hedgehog / anti-angiogenic / mTOR | BCC, lung, prostate, fungal burden | C | 2 |
| Hydroxychloroquine | Autophagy inhibition | Combinations with metabolic stressors | C | 2 |
| Cimetidine | H2 / E-selectin / NK / anti-metastatic | GI cancers, melanoma, peri-surgical | B | 2 |
| Dipyridamole | Anti-platelet / adenosine / CTC | Pairs with aspirin; anti-metastatic | C | 2 |
| Fenbendazole | Tubulin / p53 / GLUT4 | Adjunct to mebendazole; lung, colorectal | C | 2 |
| Metronidazole | Hypoxic radiosensitizer | Concurrent radiation + hypoxic tumors | D | 2 |
| DON | Glutamine antagonist | Broad (glutamine-dependent cancers) — EMERGING | C | 3 |
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This white paper is prepared for clinical and provider education purposes as part of the Root Causes SEED Program Evidence Series. It summarizes published research and does not constitute medical advice. All clinical decisions, including drug selection and dosing, should be individualized by a qualified provider. Terrain support medications described herein are used off-label; providers should ensure appropriate informed consent and documentation. Evidence grades reflect the authors' assessment of the published literature at time of writing and will be updated as new research emerges.