Generic Revia

Introduction

Revia contains the opioid‑antagonist Naltrexone and is classified under the general‑health and alcoholism medication groups. In the United Kingdom it is primarily used to support the treatment of alcohol‑use disorder and to reduce the risk of relapse in opioid‑dependent individuals after detoxification. The tablet formulation is manufactured by several licensed producers; the active ingredient is identical to that in well‑known brand‑name preparations such as Vivitrol (injectable) and the original Revia tablets. Secondary uses, for example low‑dose Naltrexone in experimental inflammatory conditions, are being investigated but are not yet approved by the Medicines and Healthcare products Regulatory Agency (MHRA).

What is Revia?

Revia is the generic version of the original brand‑name product Revia, containing the same active compound Naltrexone. It is also comparable to the long‑acting injectable Vivitrol, which delivers the same pharmacological effect over a month. Our online pharmacy provides this generic alternative as a cost‑effective treatment option. The medication is supplied as oral tablets, typically 50 mg per tablet, and is produced by manufacturers that comply with EU‑GMP standards and are listed on the MHRA’s authorised‑medicine database.

How Revia Works

Naltrexone is a competitive antagonist at μ‑opioid receptors and, to a lesser extent, κ‑ and δ‑receptors. By binding to these receptors without activating them, it blocks the euphoric and reinforcing effects of exogenous opioids and attenuates the dopamine surge associated with alcohol consumption. This antagonism reduces cravings and the rewarding sensation that drives continued use.

• Onset: Oral Naltrexone reaches peak plasma concentrations within 1 hour after ingestion.
• Duration: Therapeutic plasma levels are maintained for about 24 hours, supporting once‑daily dosing.
• Clearance: Naltrexone is metabolised primarily in the liver to an inactive 6‑β‑hydroxynaltrexone and eliminated via the kidneys; the mean elimination half‑life is 4 hours, while the active metabolite’s half‑life is approximately 13 hours.

Conditions Treated with Reiva

• Alcohol‑Use Disorder (AUD): Clinical trials in the UK and Europe have shown that a daily 50 mg dose reduces the number of heavy‑drinking days and prolongs abstinence when combined with psychosocial support.
• Opioid‑Use Disorder (OUD): After medically supervised opioid withdrawal, a 50 mg daily dose helps prevent relapse by blocking the effects of any opioid that may be inadvertently re‑used.
• Investigational Uses: Low‑dose Naltrexone (1–4 mg) is being studied for autoimmune diseases, chronic pain, and certain cancers, but these indications are not yet approved by the MHRA.

Epidemiologically, alcohol‑related harm accounts for over 7 % of all deaths in the UK, and opioid dependence affects an estimated 200 000 individuals. Access to an affordable oral antagonist can therefore have a measurable public‑health impact.

Who is Revia For?

• Adults with moderate to severe alcohol‑use disorder who have completed detoxification and are motivated to maintain abstinence.
• Individuals who have recently completed opioid detox and need pharmacological protection against relapse.
• Patients who prefer an oral regimen over the monthly injectable Vivitrol, allowing flexible dosing and easy cessation if needed.

Contra‑indications include acute hepatitis, severe hepatic impairment, and concurrent use of opioid analgesics (as Naltrexone will precipitate withdrawal). Pregnant or breastfeeding women should only use Revia if the potential benefit outweighs the risk, under specialist supervision.

Risks, Side Effects, and Interactions

Common

• Nausea, headache, dizziness, fatigue, insomnia, and mild gastrointestinal upset (diarrhoea or constipation).
• Decreased appetite or transient weight loss.

Rare

• Elevated liver enzymes (ALT/AST) – monitor liver function in patients with pre‑existing hepatic disease.
• Mood changes, including irritability or anxiety, especially during the first weeks of therapy.

Serious

• Acute opioid withdrawal: If Naltrexone is taken before complete opioid clearance, severe withdrawal (vomiting, tachycardia, hypertension, seizures) can occur.
• Hepatotoxicity: Rare cases of severe hepatitis have been reported; discontinue if liver enzymes rise >3 × ULN.
• Anaphylaxis: Extremely rare; immediate medical attention required.

Drug‑Drug Interactions

• Opioid Analgesics: Must be stopped at least 7‑10 days before initiating Revia to avoid precipitated withdrawal.
• Warfarin: Naltrexone may potentiate anticoagulant effects; monitor INR closely.
• Methadone/Buprenorphine: Dose adjustments may be required; these opioids should be discontinued before starting Revia.
• Hepatotoxic agents (e.g., isoniazid, high‑dose paracetamol): Co‑administration may increase liver risk; regular liver function tests are advised.

Practical Use: Dosing, Missed Dose, Overdose

• Standard adult dose for AUD: 50 mg tablet taken orally once daily, preferably at the same time each day.
• Standard adult dose for OUD (post‑detox): 50 mg tablet once daily, initiated after a minimum 7‑day opioid‑free period confirmed by negative urine opioid screen.
• Missed dose: If a dose is missed by less than 12 hours, take it as soon as remembered; if more than 12 hours have passed, skip the missed dose and resume the regular schedule. Do not double‑dose.
• Overdose: Symptoms may include severe nausea, vomiting, dizziness, or loss of consciousness. Seek emergency medical care immediately; supportive treatment is the mainstay, as there is no specific antidote.
• Food & Alcohol: Revia can be taken with or without food. Avoid alcohol during the first week of treatment until tolerance is assessed, as the combination may increase sedation and nausea.
• Comorbidities: In patients with hepatic impairment, dose reduction to 25 mg daily may be considered, with close monitoring of liver enzymes.

Buying Revia from Our Online Pharmacy

Revia can be purchased from our online pharmacy in the UK. Our service combines several advantages for patients who need reliable access to generic Naltrexone:

• Affordable pricing: Prices are set near manufacturer cost, delivering savings of up to 70 % compared with standard retail pharmacies.
• Verified quality: We source tablets only from MHRA‑registered overseas licensed pharmacies that adhere to EU‑GMP standards; each batch is accompanied by a certificate of analysis.
• Guaranteed delivery: Discreet packaging is dispatched via express courier (delivery within 7 days) or regular airmail (approximately 3 weeks). Tracking is provided for all orders.
• Online‑only access: Our pharmacy broker service works with a network of international suppliers, enabling patients to obtain medications that may be unavailable locally or subject to supply shortages.
• Privacy‑focused: All orders are processed without requiring personal health details beyond what is legally required, ensuring confidentiality throughout the transaction.

Choosing our online pharmacy offers a safe, cost‑effective route for adults in the UK who seek continuous treatment with Revia, especially when traditional pharmacy stock is limited.

FAQ

• What is the typical appearance of a Revia tablet?
  Revia tablets are round, film‑coated, and white to off‑white in colour, imprinted with the dosage strength (e.g., “50 mg”). The coating helps mask any bitter taste and facilitates swallowing.

• Can Revia be stored in a refrigerator?
  No. Revia should be kept at controlled room temperature (15‑25 °C). Refrigeration is unnecessary and may cause moisture condensation, which can affect tablet integrity.

• How long does the shelf‑life last after the package is opened?
  Unopened tablets retain full potency for up to 24 months from the manufacturing date. Once the bottle is opened, it is advisable to use the medication within 12 months, provided it is stored as recommended and the expiry date has not passed.

• Is there a difference between the UK and EU formulations of Naltrexone?
  The active ingredient is identical, but some manufacturers may use different inactive excipients (e.g., lactose, microcrystalline cellulose). These differences do not affect efficacy but may be relevant for patients with specific excipient intolerances.

• Can Revia affect results of workplace drug testing?
  Naltrexone is not a controlled substance and does not produce a positive result for opioids in standard immunoassay screens. However, some highly sensitive confirmatory tests may detect the drug, though it is generally considered a non‑interfering medication.

• What precautions are recommended for patients travelling with Revia?
  Carry the medication in its original packaging with the label intact. Keep it in carry‑on luggage to avoid temperature extremes in checked baggage, and bring a copy of the prescription or a doctor's note if required by customs authorities.

• Are there any known differences in efficacy between oral Revia and injectable Vivitrol?
  Both formulations provide opioid antagonism, but the injectable delivers a sustained 4‑week release, ensuring adherence. Oral Revia requires daily dosing, which can be advantageous for dose titration but may be subject to missed doses. Clinical outcomes are comparable when adherence is maintained.

• Has Naltrexone been studied in children or adolescents?
  Research in paediatric populations is limited. The MHRA has not approved Revia for use under 18 years of age, and safety data are insufficient to support routine prescribing in this group.

• What is the historical origin of Naltrexone?
  Naltrexone was first synthesised in the 196s by Endo Laboratories as part of a series of opioid‑receptor antagonists. It received FDA approval for alcohol‑dependence treatment in 1994 and was later adopted internationally, including by the UK’s NHS for selected cases.

• Can low‑dose Naltrexone be obtained as Revia?
  Low‑dose formulations (1‑4 mg) are not commercially available in the UK; they are prepared off‑label by compounding pharmacies. Revia tablets are marketed at the standard 50 mg strength, and any dose reduction must be prescribed and monitored by a specialist.

• Do any specific ethnic groups require dose adjustments for Revia?
  Pharmacokinetic studies have not identified clinically significant differences in Naltrexone metabolism across ethnicities. However, individuals of Asian descent may have a slightly higher prevalence of certain hepatic enzyme polymorphisms, so liver function should be monitored regularly.

• Are there any known interactions between Revia and over‑the‑counter supplements?
  Herbal products such as St. John’s wort may induce hepatic enzymes, potentially lowering Naltrexone plasma levels. Patients should disclose all supplements to their healthcare provider to assess any need for monitoring or dose adjustment.

Glossary

Opioid Antagonist

A substance that binds to opioid receptors without activating them, thereby blocking the effects of opioid agonists such as morphine or heroin.

Hepatotoxicity

Chemical‑induced liver damage, often identified by elevated liver enzymes (ALT/AST) in blood tests.

Pharmacokinetics

The study of how a drug is absorbed, distributed, metabolised, and excreted by the body.

Psychosocial Support

Non‑pharmacological interventions (e.g., counseling, support groups) that complement medication in treating substance‑use disorders.

⚠️ Disclaimer

The information provided about Revia is for general knowledge only. It does not replace professional medical consultation. All treatment decisions should be made under the supervision of a qualified healthcare provider. We assume all readers are responsible adults capable of making informed decisions about their health. Our online pharmacy offers access to Revia for individuals who may have limited availability through traditional pharmacies, prescription‑based insurance schemes, or who are seeking affordable generic alternatives. Always consult your doctor before starting, changing, or discontinuing any medication.