Desyrel (Trazodone): Patient-Friendly Guide for Australia
Basic Product Information
| International Non-proprietary Name (INN) | Trazodone |
| Brand Names in Australia | Desyrel, Trazodone Sandoz, APO-Trazodone |
| ATC Code | N06AX05 |
| Available Forms & Strengths | Tablets: 50 mg, 100 mg, 150 mg* |
| Manufacturers | Viatris, Sandoz, Apotex and others |
| Prescription Status | Prescription only (S4) |
| Pack Sizes | 20, 30, 60 tablets (varies by brand) |
| Reimbursement Status | Some brands listed on PBS for major depressive disorder |
Mechanism of Action
Patient-friendly explanation: Trazodone, the active ingredient in Desyrel, helps balance natural chemicals in the brain called neurotransmitters—mainly serotonin. By preventing the early re-uptake (removal) of serotonin, trazodone helps improve mood, reduce anxiety, and can support better sleep.
For specialists: Trazodone is classified as a serotonin antagonist and reuptake inhibitor (SARI). It selectively inhibits serotonin reuptake and antagonises 5-HT2A, 5-HT2C, and alpha-adrenergic receptors. This provides both antidepressant and anxiolytic effects and facilitates sleep initiation via antihistaminic activity.
Pharmacokinetics
- Absorption: Rapid, with a bioavailability of about 65% when taken orally.
- Peak Plasma Concentration: 1–2 hours after ingestion.
- Distribution: Protein binding ~90–95%.
- Metabolism: Mainly in the liver via CYP3A4 to active metabolite m-chlorophenylpiperazine (mCPP).
- Elimination: Primarily via urine (~70%) and faeces (~20%).
- Half-life: Initial: 3–6 hours; terminal: 5–13 hours.
- Duration of action: Up to 24 hours for sustained effects.
Use in Everyday Life and Best Practices
Trazodone is commonly prescribed by Australian GPs and psychiatrists to treat major depressive disorder, insomnia related to depression, and, less commonly, anxiety. It is often chosen when patients have difficulty tolerating other antidepressants due to sexual side effects or sleep disturbances.
Typical doses:
- For depression: 150 mg daily in divided doses, gradually titrated based on response and tolerance (max 600 mg in hospital).
- For insomnia (off-label): A lower dose such as 25–100 mg taken at night may be recommended.
- Elderly or frail: Start at lower doses, increase with caution.
Your doctor will adjust your dose gradually. Swallow tablets whole with water, and take them around the same time each day for best results.
Dosing: Morning vs Evening
- Evening dosing: Most Australians take trazodone at night due to its sedative effects, which can help with sleep.
- Morning dosing: Not usually recommended as it may cause drowsiness and affect daily activities.
- Tip: Take your dose after your main evening meal to reduce stomach upset and daytime sleepiness.
- Always take as directed by your doctor. If you miss a dose, do not double up—just take the next as scheduled.
Taking with Food or on an Empty Stomach
Taking trazodone with food (such as a typical Australian dinner of meat and vegetables, pasta, or a vegetarian meal) can improve absorption and reduce gastrointestinal side effects like nausea. Avoid high-fat or overly rich foods immediately before your dose, as this can delay absorption in some cases. If you experience stomach discomfort when taking Desyrel, always opt for a light snack with your medication.
Interaction Warnings
| Category | Examples | Interaction Outcome |
|---|---|---|
| Alcohol | Beer, wine, spirits | Increased sedation, risk of overdose. Avoid combining. |
| Other Medications | SSRIs (fluoxetine, sertraline), MAOIs, benzodiazepines, antipsychotics, antihypertensives, warfarin, St John's Wort | Risk of serotonin syndrome, increased drowsiness, blood pressure changes, bleeding |
| Food | Grapefruit, grapefruit juice | Can raise trazodone levels and side effects |
| Other Substances | Narcotics, strong pain relief (opioids, codeine) | Increased risk of drowsiness and breathing problems |
- Always tell your doctor or pharmacist about all medicines you take, including over-the-counter and herbal medicines.
- Do not stop or start any medication without your doctor's advice.
Indications
| Indication | Official (TGA) | Off-label |
|---|---|---|
| Major depressive disorder (MDD) | Yes | - |
| Insomnia (secondary to depression or anxiety) | - | Common |
| Generalised Anxiety Disorder (GAD) | - | Occasionally |
| PTSD, agitation in dementia, fibromyalgia | - | Case-by-case |
Dosing According to Clinical Indication
| Population | Indication | Typical Starting Dose | Usual Range | Maximum |
|---|---|---|---|---|
| Adult | MDD | 75–150 mg/day (usually at night) | 150–300 mg/day | 600 mg/day (in hospital) |
| Adult | Insomnia (off-label) | 25–50 mg at bedtime | up to 100 mg at bedtime | 100 mg/day |
| Elderly | Any | 25–50 mg at bedtime | 100–150 mg/day | 300 mg/day |
| Paediatric (over 12 years, rare) | Depression, as per specialist | 1–2 mg/kg/day in divided doses | Up to 6 mg/kg/day | - |
Safety Profile and Side Effects
| Frequency | Side Effect / Warning | Advice |
|---|---|---|
| Common (>1/10) | Drowsiness, dry mouth, dizziness, headache, blurred vision, constipation | Avoid driving or machinery if affected; see doctor if severe |
| Uncommon | Low blood pressure (esp. on standing), fatigue, rash | Rise slowly from sitting/lying; consult your healthcare professional |
| Rare | Priapism (prolonged, painful erection in males), serotonin syndrome, liver changes, irregular heartbeat (QT prolongation) | Seek urgent medical help; report new symptoms promptly |
| Other | Overdose can cause extreme drowsiness, breathing issues, heart rhythm changes | Emergency (call 000 or attend ED immediately) |
Warnings:
- Not recommended during pregnancy or breastfeeding unless advised by a doctor
- Monitor for mood changes, suicidal thoughts—seek medical help if concerned
- Regular medical check-ups recommended (blood pressure, blood tests, ECG if indicated)
Guidelines for Proper Use in Australia
- Always take Desyrel as prescribed by your doctor or pharmacist.
- Avoid drinking alcohol; it increases risk of drowsiness and other side effects.
- If you have a history of heart conditions, inform your healthcare provider.
- Do not cut or crush tablets unless advised by your pharmacist (some brands are scored, some are not).
- If side effects persist or worsen, do not stop abruptly—consult your doctor for advice.
- Keep out of reach of children and store below 25°C in a dry place.
- If you plan to travel within Australia, keep medication in its original packaging with a pharmacy label.
- Check with your pharmacist before using over-the-counter medicines or herbal supplements.
Alternative Treatment Options
- Other antidepressants reimbursed by PBS:
- SSRIs: Escitalopram, sertraline, fluoxetine (widely used, well-tolerated, but can cause sexual dysfunction/insomnia)
- SNRIs: Venlafaxine, desvenlafaxine (can boost energy, but may affect blood pressure)
- Mirtazapine: Helpful if poor sleep or appetite loss (more sedating, may cause weight gain)
- Amitriptyline: Useful for depression and some chronic pain, but higher anticholinergic risks, especially in elderly
- Comparative overview:
Trazodone (Desyrel) is often considered when sleep improvement is a priority or if other antidepressants have caused problematic side effects. It has a lower risk of sexual dysfunction than most SSRIs or SNRIs and is less likely than amitriptyline to cause anticholinergic side effects.
Legal Registration and Reimbursement Status in Australia
- Regulatory approval: Registered by the Therapeutic Goods Administration (TGA) for depression
- Prescription status: Schedule 4 (Prescription Only Medicine)
- PBS Coverage: Selected brands reimbursed for major depressive disorder
- Supply: Legally supplied only by registered doctors and pharmacists in Australia plus community pharmacies
- Notifiable disease monitoring: Only necessary if serious side effects occur (Therapeutic Goods Administration reporting)
Latest Research and Clinical Guidelines (2022–2025)
- NICE and Royal Australian and New Zealand College of Psychiatrists (RANZCP) guidelines recognise trazodone as a second-line or adjunctive therapy for depression, particularly where insomnia is a complicating factor.
- Recent meta-analyses (Gao K et al., 2023; J Clin Psychopharmacol; and NICE Clinical Knowledge Summaries, 2024) support trazodone's utility for sleep initiation and depression, with a low rate of sexual side effects compared to SSRIs.
- Emerging evidence (JAMA Psychiatry, 2023) suggests trazodone's benefit for short-term insomnia in depression, though long-term use for primary insomnia is not officially recommended due to limited high-quality evidence.
Availability and Delivery: Pack Sizes & Pricing
| City/Region | Typical Delivery Time* | Popular Pack Size | Indicative Price† |
|---|---|---|---|
| Sydney | 1–2 working days | 30 x 100 mg | $12–$25 |
| Melbourne | 1–2 working days | 30 x 50 mg | $10–$21 |
| Brisbane | 1–3 working days | 20 x 150 mg | $15–$30 |
| Perth | 2–4 working days | 60 x 100 mg | $22–$42 |
| Regional/rural | 3–5 working days | Varies | Check with local pharmacy |
Frequently Asked Questions (FAQ)
- How long does it take for trazodone (Desyrel) to start working?
For depression, some improvement may be noticed in 1–2 weeks, but full effect can take up to 4–6 weeks. For sleep, effects may appear within the first few days. - Can Desyrel be used long-term for insomnia?
While trazodone is often prescribed short-term for sleep problems, it is not officially approved for long-term insomnia. Your doctor may recommend alternatives if your sleep issues persist. - Is it safe to drink alcohol while taking Desyrel?
No, alcohol can increase drowsiness and risk of side effects. It's safest to avoid alcohol while on this medication. - What should I do if I miss a dose?
If you miss a dose, take it as soon as you remember—unless it's almost time for your next dose. Do not double up. If in doubt, check with your pharmacist or doctor. - Can I drive while using trazodone?
Trazodone can cause drowsiness, especially when you first start taking it or after dose increases. Do not drive or operate machinery if you feel sleepy or dizzy.
For more information or if you experience side effects, always consult your pharmacist or doctor. Further resources are available from the Therapeutic Goods Administration (TGA) and your nearest community pharmacy.
