Compound Interaction Checker: Make Stacks Safer with Evidence‑Based Alerts

TL;DR: Drug Interaction Checker Medscape Guide

Most “stack builders” stop at listing compounds. CycleVitals goes further: select two or more compounds and get a risk score, why it’s risky (mechanisms), when it’s riskiest (half‑life overlap windows), and what to do about it (monitoring and safer alternatives). Built for adults who want to reduce harm, not roll the dice.

Disclaimer: CycleVitals provides tracking and educational tools only. We do not provide medical advice, diagnosis, or treatment. Always consult a qualified clinician before starting, stopping, or modifying any protocol.

Why interactions matter more than ingredients

Most problems don’t come from a single compound—they come from interactions:

• Additive strain (e.g., multiple hepatotoxic or lipotoxic agents stacking liver or lipid risk)

• Synergistic effects (androgenic + sympathomimetic → blood pressure/HR stress)

• Timing collisions (overlaps at peak concentration, not planned on paper)

• Downstream recovery (harder PCT and endocrine rebound when exposures overlap)

When two drugs are combined, their interactions can lead to increased adverse effects or similar side effects, potentially amplifying or diminishing the desired effects of each medication.

Spreadsheets list compounds. Interaction intelligence connects mechanisms, timing, and potential outcomes. Understanding how two drugs interact is crucial to avoid unexpected side effects and ensure the desired effects of therapy.

Types of interactions you should know about

When it comes to prescription drugs, over-the-counter medicines, and supplements, understanding the different types of drug interactions is essential for your safety and the effectiveness of your treatment. Drug interactions can occur in several ways, and being aware of them can help you avoid dangerous side effects and ensure your medications work as intended.

1. Drug-drug interactions:These happen when one drug alters the way another drug works in your body. Drug-drug interactions can lead to reduced effectiveness, unexpected side effects, or even dangerous reactions. For example, taking two or more drugs that both affect blood pressure can increase your risk of high or low blood pressure, while combining blood thinners with certain painkillers can increase bleeding risk. Most drug interactions occur when multiple prescription medications, over-the-counter drugs, or supplements are taken together.

2. Drug-food interactions:Some foods and drinks can interact with medications, changing how your body absorbs or processes them. A classic example is grapefruit juice, which can increase the levels of certain drugs in your bloodstream, leading to more side effects. Other foods, like those high in vitamin K, can interfere with blood thinners. Always check drug packages for food warnings and ask your healthcare professional if you should take your medicine on an empty stomach or avoid certain foods.

3. Drug-disease interactions:Your health conditions can also affect how drugs work. For instance, some medications may worsen high blood pressure or interact with other health conditions, making them less safe or effective. It’s important to tell your doctor about all your health conditions before starting a new medication.

Supplements and herbal remedies:Dietary supplements, herbal supplements, and vitamins can also interact with prescription drugs and over-the-counter medicines. St. John’s wort, for example, can reduce the effectiveness of many medications, while some herbal remedies may increase the risk of dangerous side effects when combined with other drugs.

How the CycleVitals Interaction Checker works

Step 1 — Select compounds. Choose two or more steroids, SARMs, or other PEDs from our growing database. The CycleVitals drug interaction checker helps users identify possible drug interactions between selected compounds.

Step 2 — We map mechanisms & evidence. Our model reviews mechanism categories (hepatic strain, lipid impact, hematology, cardio/renal, neuro, endocrine) and aligns them with peer‑reviewed and reputable reference sources. The model evaluates potential interactions and highlights any affected drug based on mechanism and evidence.

Step 3 — We calculate timing windows. Using half‑life profiles, we flag overlap zones where peaks/troughs magnify risk.

Step 4 — We score the interaction. You’ll see LOW / MODERATE / HIGH with plain‑English rationale.

Step 5 — We suggest safer moves. Monitoring priorities, behavioral mitigations, and alternative planning ideas (e.g., spacing, avoiding duplicate risk pathways). These strategies help users avoid drug interactions and manage risk proactively.

Step 6 — Save & export. Keep the interaction note with your cycle; export a clinician‑friendly summary.

We do X by Y: We make stacks safer by uniting interaction science, half‑life math, and practical mitigations in one screen.

What the risk score actually means

• LOW: Overlap is unlikely to elevate risk beyond each compound’s baseline. Maintain monitoring.

• MODERATE: Additive mechanisms or timing suggest elevated caution. Tighten monitoring; consider spacing or substitution.

• HIGH: Mechanism conflicts or peak collisions suggest significant risk. Re‑plan (timing, dose, or compound choice) and discuss with a clinician. Identifying important drug interactions at this level is essential to prevent serious health risks and ensure safe medication use.

Each score is accompanied by evidence notes (mechanism rationale) and timing considerations (where overlap peaks).

The “why” behind the warnings (mechanism categories)

• Liver & lipid strain: oral 17‑aa agents; LDL↑/HDL↓ profiles; ALT/AST effects.

• Hematology: erythrocytosis/hematocrit changes and downstream viscosity/BP issues.

• Cardiovascular: BP, HR, endothelial function, QTc considerations with stimulatory stacks.

• Renal: RAAS and BP‑related burden; hydration/electrolyte considerations.

• Neuro: mood/sleep impacts; stimulant synergy; CNS agitation.

• Endocrine: HPTA suppression depth, recovery difficulty, and PCT implications.

We surface the mechanism, not just a red badge—so you know why to change the plan.

Timing considerations: half‑life overlap windows

Even “mild” agents can add up at the wrong time. CycleVitals visualizes:

• Accumulation → steady‑state (when levels build and stabilize)

• Peak overlap windows (days where multiple peaks coincide)

• Clearance (how long exposures persist into PCT)

This helps you avoid unintentional peak collisions and plan recovery timing more realistically.

What you’ll see in the UI (quick tour)

• Compound cards with aliases and quick risk tags (e.g., Liver: MODERATE; Cardio: HIGH) help users quickly spot potential drug interaction and drug drug interaction risks.

• Timing Considerations callouts where peaks collide

• Required Monitoring badges (evidence‑based monitoring protocols)

• Mitigation notes (space doses; avoid duplicate risk path; consider alt compound)

Screenshot depicts sample UI elements for illustration.

This tool is designed to support both patients and healthcare professionals, including pharmacists, in managing medication safety.

Practical mitigations we’ll suggest (examples)

• Don’t double down on the same risk path. Avoid stacking two agents that both drive the same red‑zone (e.g., liver + liver).

• Plan spacing, not just dosing. Enforce gaps where peaks would otherwise collide.

• Monitor with intention. Prioritize BP, lipid panel, liver enzymes, hematocrit/hemoglobin—frequency depends on individual factors.

• Re‑think the objective. If the goal is strength, consider an alternative that doesn’t hit the same toxicity path.

• Document everything. Keep logs so patterns are obvious over time. Make sure to keep a record of all the medicines you are taking, including prescription drugs, OTC products, vitamins, and supplements, to help identify and prevent interactions.

(None of the above is medical advice.)

Who it’s for

• TRT + adjunct planning who want to avoid accidental risk spikes

• Performance users who want objective, harm‑reduction‑first insights

• Coaches/clinicians who want structured, evidence‑oriented summaries

Why this beats spreadsheets & generic calculators

• Contextual: We look at interactions, not just single‑compound notes. Most drugs can interact in complex ways, so a dedicated tool is more effective than spreadsheets for managing these risks.

• Temporal: Half‑life math highlights when risks are highest.

• Actionable: Your score comes with what to do next.

• Portable: Save to your cycle; export clinician‑friendly PDFs/CSV/JSON.

Privacy & control

• Data is yours; export anytime (PDF/CSV/JSON).

• No selling personal data.

• You can delete your account data from settings.

Get started

Build a plan you can defend. The Compound Interaction Checker can be used to check interactions for common medicines as well as performance-enhancing compounds. Try the Compound Interaction Checker free in CycleVitals. → Start free | See all features

FAQs

Does CycleVitals tell me what to take?
No. We provide educational interaction insights so you can discuss options with a clinician. For personalized medical advice, always consult a licensed physician or other appropriately qualified health care provider.

How accurate is the risk score?
It reflects mechanism‑level evidence, compound profiles, and timing math. Individual responses vary; use it as a structured conversation aid—not a diagnosis.

Does it cover SARMs and non‑steroidal PEDs?
Yes. Coverage is expanding; unsupported compounds will be labeled as such until evidence thresholds are met. The tool also helps identify interactions with herbs, such as john's wort, and other supplements.

Can this replace blood work?
No. Interaction intelligence complements, not replaces, objective lab monitoring. The tool can help flag potential interactions with substances like alcohol and orange juice, but clinical monitoring is still necessary.

Will this help with PCT planning?
Yes. Interaction outputs inform PCT Builder timing and emphasis (e.g., watchpoints), but final decisions should be clinician‑guided. Be cautious about drinking alcohol or using herbal supplements during PCT, and consult a healthcare provider if unsure.