Rejuvenate — Safety Information
Who should not take Rejuvenate without medical guidance
- Active systemic infection or sepsis — L-Arginine raises nitric oxide, which can worsen haemodynamic instability during systemic infection. Do not use without direct medical supervision.
- Severe renal impairment — High-dose amino acids require adequate renal clearance. L-Citrulline is converted to L-Arginine in the kidneys; impaired renal function may reduce conversion and increase amino acid accumulation. Consult your nephrologist.
- Severe hepatic impairment — L-Arginine is metabolised hepatically. Impaired liver function may reduce clearance. Consult your specialist before use.
- Recurrent herpes simplex (cold sores or genital herpes) — L-Arginine is required for herpes simplex virus replication. High-dose arginine supplementation may trigger outbreaks in susceptible individuals. If you have recurrent HSV, seek medical advice before use. Concurrent lysine supplementation may reduce this risk — discuss with your clinician.
- Post-organ transplant (taking immunosuppressants) — L-Arginine can stimulate immune function, which may interfere with immunosuppressive therapy. Do not use without guidance from your transplant team.
- Pregnancy and breastfeeding — Safety has not been established in pregnancy or breastfeeding. Consult your midwife or obstetrician before use.
- Children — Not suitable for use in children.
Known and potential drug interactions
The following interactions are based on published pharmacological data for the active ingredients in Rejuvenate. This list is a guide, not exhaustive medical advice. Always disclose supplement use to your prescriber.
| Drug / Drug class | Ingredient involved | Interaction | Risk level |
|---|---|---|---|
| Anticoagulants (warfarin, heparin, apixaban) |
Turmeric (curcumin) | Curcumin inhibits platelet aggregation and may potentiate anticoagulant effects, increasing bleeding risk. INR should be monitored more frequently if warfarin is co-administered. | High |
| Antiplatelet drugs (aspirin, clopidogrel, dipyridamole) |
Turmeric (curcumin) | Additive inhibition of platelet aggregation. Risk of increased bruising or bleeding, particularly post-surgery. | High |
| PDE5 inhibitors (sildenafil, tadalafil, vardenafil) |
L-Arginine, L-Citrulline | Both PDE5 inhibitors and arginine/citrulline act on the nitric oxide pathway. Combination can cause excessive vasodilation and severe hypotension. Do not co-administer without medical supervision. | High |
| Nitrate medications (GTN spray, isosorbide mono/dinitrate) |
L-Arginine, L-Citrulline | Nitrates also act via the NO pathway. Additive effect may cause severe hypotension. Inform your prescriber. | High |
| Antihypertensives (ACE inhibitors, calcium channel blockers, beta-blockers) |
L-Arginine, L-Citrulline | Arginine and citrulline lower blood pressure via nitric oxide. Additive blood pressure reduction may occur. Monitor blood pressure more frequently. | Medium |
| Antibiotics (tetracyclines, quinolones e.g. ciprofloxacin) |
Zinc, Magnesium | Zinc and magnesium can chelate with these antibiotics and reduce their absorption. Separate administration by at least 2–3 hours. | Medium |
| Bisphosphonates (alendronate, risedronate) |
Magnesium | Magnesium can reduce bisphosphonate absorption. Separate administration by at least 2 hours. | Medium |
| Thiazide diuretics (bendroflumethiazide, hydrochlorothiazide) |
Vitamin D3 | Thiazide diuretics reduce urinary calcium excretion. In combination with high-dose vitamin D, this may increase the risk of hypercalcaemia. Monitor calcium levels. | Medium |
| Digoxin | Vitamin D3 | Hypercalcaemia secondary to high vitamin D may increase the risk of digoxin toxicity (arrhythmia). Monitor calcium and digoxin levels. | Medium |
| Copper supplements / copper-dependent enzymes | Zinc | High zinc intake competitively inhibits copper absorption. Extended use of zinc supplements without copper supplementation may lead to copper deficiency. Risk is low at short course durations but increases with prolonged use (>8 weeks). | Low |
| Immunosuppressants (ciclosporin, tacrolimus, mycophenolate) |
L-Arginine | Arginine can stimulate T-cell proliferation and immune activation, potentially counteracting immunosuppressive therapy. Not recommended post-transplant without specialist approval. | High |
Risk levels are assigned based on pharmacological plausibility and published case evidence, not incidence rates. Always disclose Rejuvenate use to your prescriber and pharmacist.
Safe upper levels — Zinc and Vitamin D3
Two ingredients in Rejuvenate are dosed above 100% NRV and have established safe upper intake levels in the UK. Check your combined daily intake if you take other supplements.
UK safe upper level: 25 mg/day. Do not combine with other zinc-containing supplements without checking your total daily intake. Long-term intakes above 25 mg/day may impair copper absorption and immune function.
UK safe upper level: 100 µg (4,000 IU)/day. If you take a separate vitamin D supplement, check your combined daily total does not exceed this level. Prolonged intakes above the upper level may cause hypercalcaemia.
Special populations
Pregnancy and breastfeeding
The safety of high-dose L-Arginine, L-Citrulline, and supplemental turmeric in pregnancy has not been adequately studied. Do not use Rejuvenate during pregnancy or breastfeeding without medical advice.
Children and adolescents
Rejuvenate is not formulated for, and should not be used by, children or adolescents under 18.
Older adults
No specific contraindication; however, older adults are more likely to be taking multiple medications with which the interactions described above are relevant. A full medication review with your GP or pharmacist before starting Rejuvenate is recommended.
People with recurrent herpes simplex
L-Arginine is required for replication of the herpes simplex virus. Individuals who experience recurrent cold sores (HSV-1) or genital herpes (HSV-2) may find that high-dose arginine supplementation triggers outbreaks. If this applies to you, seek medical advice before use. Some evidence supports concurrent supplementation with L-Lysine (an arginine antagonist) to reduce this risk — discuss with your clinician.
General safety information
- Do not exceed one 150 ml shot per day.
- Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.
- Store below 25°C. Keep out of direct sunlight.
- Refrigerate after opening. Consume promptly once opened.
- Keep out of the reach of young children.
- Discontinue use and consult a healthcare professional if you experience any adverse reaction.
Reporting adverse reactions
If you experience an adverse reaction that you believe may be related to Rejuvenate, please contact us at hello@cclabs.uk with a description of the reaction, the date it occurred, and any other supplements or medications you were taking at the time.
Serious adverse reactions to food supplements can also be reported to the MHRA Yellow Card scheme.
This page is provided for information purposes only and does not constitute medical advice. CCLabs Ltd is not liable for any harm arising from use of Rejuvenate contrary to the guidance provided on this page. Always consult a qualified healthcare professional before starting any supplement, particularly if you have an underlying medical condition or take prescription medication.