Restfine (Melatonin)

Restfine (Melatonin): Patient-Friendly Information for Australian Patients

Basic Product Information

Mechanism of Action

For Patients: Melatonin is a naturally occurring hormone made by your body's pineal gland. It helps regulate your sleep-wake cycle—sometimes called your "body clock." By supplementing with melatonin (such as Restfine), you're helping your body signal that it's time for sleep, which can make it easier to fall asleep and stay asleep.

For Healthcare Professionals: Melatonin acts as a chronobiotic, binding to MT1 and MT2 receptors in the suprachiasmatic nucleus (SCN) of the hypothalamus to promote sleep onset and regulate circadian rhythms. It also possesses antioxidant properties, but the main clinical action is sleep–wake modulation.

Pharmacokinetics

• Absorption: Oral melatonin is rapidly absorbed, with peak plasma levels reached in about 30–120 minutes after ingestion.
• Metabolism: Extensively metabolised in the liver, mainly by CYP1A2.
• Elimination: Mostly excreted as 6-sulphatoxymelatonin in urine.
• Duration of Action: Short-acting forms: up to 4 hours; Prolonged-release (e.g. Restfine): up to 8–10 hours.
• Half-life: Short-acting: 30–50 minutes; Prolonged-release: sustained plasma levels over several hours.
• Considerations: Hepatic impairment may increase melatonin exposure.

Use in Everyday Life and Best Practices

In Australia, melatonin is commonly used to manage sleep disorders, especially for older adults over 55, people with insomnia, and those experiencing jet lag or shift work sleep disorder. Prolonged-release forms (e.g. Restfine 2 mg) are often preferred for maintaining sleep throughout the night.

1. Usual Dose: Start with 2 mg taken 1–2 hours before bedtime. Only increase under medical supervision.
2. Swallow whole: Do not crush or chew prolonged-release tablets.
3. Regular Dosing: For best results, take at the same time every night.
4. Short-Term Use: Often recommended for 2–13 weeks, depending on the condition and doctor's advice.

Dosing in the Morning vs Evening

Restfine and most melatonin products should be taken in the evening, 1–2 hours before your intended bedtime. Taking melatonin in the morning can disrupt your natural circadian rhythm and may cause daytime drowsiness.

• Evening Dosing: Aligns with your body's natural melatonin increase. Promotes sleep onset and maintenance. This is the standard and recommended approach in Australia.
• Morning Dosing: Not recommended for insomnia. May rarely be directed by a sleep specialist for circadian rhythm disorders—always follow specialist advice.
• Tip: Set a daily reminder to increase dosing regularity.

Taking with Food or on an Empty Stomach

Food can delay melatonin absorption by up to 60 minutes but does not reduce its overall effect. In Australia, taking Restfine after a light meal or on an empty stomach is generally recommended for faster onset of action. Heavy, fatty, or late dinners (especially cheese and red meat) may slow absorption.

• Best Practice: Take Restfine around 1–2 hours after your evening meal.
• Heavy Meals: Avoid heavy meals or alcohol close to bedtime when using melatonin.
• For Australians: A light evening meal (fish, salad, grains) fits well with melatonin dosing.

Interaction Warnings

Indications

Dosing According to Clinical Indications

Safety Profile and Potential Side Effects

• Very Common/Expected:
  • Drowsiness (especially if taken at the wrong time)
  • Headache
  • Fatigue
• Common:
  • Nausea or gastrointestinal upset
  • Mild dizziness
  • Vivid dreams
• Uncommon/Rare (But Reported):
  • Allergic reaction (rash, swelling)
  • Daytime sleepiness (especially with higher doses)
  • Mood changes, irritability
  • Hormonal effects (rare, with high or prolonged doses)
• Warnings:
  • Use caution if you have severe liver disease, autoimmune conditions, or epilepsy – always discuss with your doctor
  • Do not drive or operate machinery for several hours after taking melatonin

Guidelines for Proper Use in Australia

1. Only use Restfine as prescribed by your doctor or pharmacist. Do not self-medicate, especially in children or if you take regular medication.
2. Store below 25°C, out of direct sunlight and away from children.
3. If you miss a dose, do not double up the next night – simply resume your usual schedule.
4. Keep a sleep diary to monitor your sleep quality and share with your healthcare provider if symptoms persist.
5. For shift workers and travellers, plan dosing according to your sleep schedule – your pharmacist can help optimise timing for your situation.
6. Dispose of unused or expired medication via your local pharmacy's return scheme.

Alternative Treatment Options

• Z-drugs: (zopiclone, zolpidem) – effective but higher risk of dependence, amnesia, and next-day sedation. PBS-reimbursed for specific indications, more restrictions.
• Benzodiazepines: (temazepam, diazepam) – effective in the short term, strong risk of dependence, withdrawal, and cognitive effects. Prescription only; generally not first-line.
• Antidepressants: (doxepin, mirtazapine, amitriptyline) – used off-label for insomnia in lower doses, especially where depression coexists. More side effects.
• Antihistamines: (promethazine, doxylamine) – can be sedating, but risk of hangover effect and anticholinergic side effects; non-reimbursed.
• Non-drug measures (CBT-I): Cognitive–behavioural therapy for insomnia is highly recommended as the first-line, durable, safe intervention (covered by Medicare for eligible patients).
• Suvorexant: A newer orexin receptor antagonist; available in Australia, useful where other options fail, script-only.

Legal, Regulatory and Reimbursement Status in Australia

• Registration: Melatonin prolonged-release ("Circadin", "Restfine") is registered by the TGA for insomnia in patients aged 55 years and older. Short-acting or supplementary melatonin forms are not always TGA-approved or standardised; check labelling and retain purchase receipts.
• Availability: Prescription-only for most forms; some OTC melatonin is available in pharmacy-only sections, subject to state regulations.
• Reimbursement: Melatonin products generally not subsidised by the Pharmaceutical Benefits Scheme (PBS) as of June 2024. Private prescription cost applies.
• URPL, MZ equivalence: Not relevant for Australia; refer to TGA and PBS for regulations.
• Driving and Work Safety: Melatonin is not a controlled drug in Australia, but caution is strongly recommended after use due to possible next-day drowsiness. Notifiable for some high-risk jobs (pilots, heavy machinery operators).

Latest Research and Clinical Guidance (2022–2025)

• Australian Sleep Association Guideline (2022-2024): Melatonin prolonged-release is first-line for insomnia in adults over 55 where CBT-I is not sufficient or not available. Short-acting melatonin may be considered off-label for shift workers or jet lag.
• Paediatric Use: A 2023 RCT published in "The Lancet Child & Adolescent Health" supports safety and efficacy in children with autism and sleep problems, though specialist monitoring is recommended.
• Meta-analysis (JAMA, 2024): Melatonin demonstrates modest efficacy in reducing sleep latency and increasing total sleep time compared to placebo; best for initiating sleep.
• UK NICE Sleep Guidance Update (2023): Recommends melatonin after non-drug interventions fail; reemphasises limitation to short-term use and strict indication.
• Ongoing Studies: Current research is focused on use in delayed sleep phase syndrome and neurodevelopmental disorders.

Availability and Delivery

FAQ – Frequently Asked Questions

1. Q: Is melatonin safe for long-term use?
   A: For most adults, melatonin is safe for up to 13 weeks under medical supervision. Prolonged, unsupervised use (especially at high doses) is not recommended due to lack of long-term safety data. See your doctor if you intend to use melatonin beyond three months.
2. Q: Is Restfine suitable for children?
   A: Only under specialist paediatric advice. Restfine and most prescription forms are not TGA-approved for general use in children unless prescribed by a paediatrician or sleep specialist, especially for neurodevelopmental disorders.
3. Q: Will melatonin help me stay asleep all night?
   A: Prolonged-release formulations (like Restfine) are designed to help you both fall asleep and remain asleep. However, the effect varies by person. Good sleep hygiene and regular bedtimes will help maximise benefits.
4. Q: Can I drive after taking melatonin?
   A: You should avoid driving, cycling, or operating machinery for at least 4–6 hours after taking melatonin, as drowsiness and impaired concentration can persist.
5. Q: Are there foods or drinks I should avoid?
   A: Avoid caffeine in the afternoon and evening, as well as alcohol within three hours of bedtime, to help melatonin work effectively. Heavy, rich or spicy meals late in the evening may also delay melatonin's effect.

Further Information

Always consult your pharmacist or doctor if you have questions about Restfine or any other sleep medications. For emergencies or severe side effects, contact 000 or attend your nearest emergency department.