Stillnox is the trade name for zolpidem tartrate, a prescription-only hypnotic commonly used to treat short-term insomnia. It belongs to the non-benzodiazepine sedative-hypnotic class, often referred to as Z-drugs, alongside zopiclone and eszopiclone.
In Hong Kong, Stillnox is regulated under the Pharmacy and Poisons Ordinance (Cap. 138) as a Prescription-Only Medicine (P1 poison), meaning it cannot be obtained without a licensed doctor’s prescription.
Clinical Use
In clinical settings, physicians in Hong Kong generally prescribe zolpidem for:
- Sleep-onset insomnia (difficulty falling asleep)
- Transient sleep disturbance due to stress or shift work
- Short-term treatment of acute insomnia episodes
Its onset of action is typically within 15–30 minutes, with a duration of about 6–8 hours, depending on the formulation.
The NHS (UK) notes that zolpidem should be used for the shortest period possible, generally not exceeding 2–4 weeks, to avoid dependence and rebound insomnia (NHS Zolpidem Guidance).
Legal Status of Stillnox in Hong Kong
- Category: Part I Poison (Prescription-Only)
- Availability: By prescription from registered medical practitioners and dispensed by licensed pharmacies
- Importation: Requires valid medical documentation; unregistered imports can be confiscated under Hong Kong Customs regulations (Customs.gov.hk – Controlled Substances)
Patients should be aware that possession or importation of unregistered foreign versions of zolpidem — even if medically prescribed elsewhere — may be subject to customs scrutiny.
Why Some Sleep Medicines Are Restricted
Sleep-inducing medications act on gamma-aminobutyric acid (GABA) receptors to reduce neuronal activity, promoting relaxation and drowsiness. However, these mechanisms also carry risks:
- Dependence and tolerance with long-term use
- Residual drowsiness, affecting coordination and driving
- Memory disturbance or parasomnias in rare cases
Therefore, regulatory authorities like the World Health Organization (WHO) and Hong Kong’s Department of Health emphasise cautious, physician-supervised use.
(WHO Guidelines for the Treatment of Insomnia, 2023).
Sleep Medication Landscape in India: Legal Comparisons
While zolpidem (Stillnox) is available by prescription in India, the market also includes related Z-drug hypnotics, such as zopiclone, eszopiclone, and branded generics like Zop 7.5 mg.
These medications share similar pharmacodynamics — they act as GABA-A receptor agonists to induce sleep — but differ slightly in duration, side-effect profile, and taste tolerability.
Zopiclone
Zopiclone is one of the earliest Z-drugs and has a half-life of 5–6 hours, making it suitable for patients who struggle with maintaining sleep rather than initiating it.
It is classified as a Schedule H prescription medicine under the Drugs and Cosmetics Act 1940 in India, meaning it must be dispensed only on a doctor’s prescription.
Eszopiclone (Hypnite)
Eszopiclone, the S-enantiomer of zopiclone, offers a slightly longer duration of action and may produce fewer metallic aftertastes — a common complaint with zopiclone.
It is marketed in India under brand names such as Hypnite and is also a Schedule H drug, legally available through prescription only.
Zop 7.5 mg
A brand formulation of zopiclone, Zop 7.5 mg is widely prescribed for transient or short-term insomnia. Like other hypnotics, it is intended for short courses only (usually 7–14 days) to minimise tolerance.
In clinical practice across South Asia, physicians often prefer zopiclone-based therapy when patients experience difficulty maintaining sleep, while zolpidem (Stillnox) is chosen for rapid sleep induction.
Key Pharmacological Differences
| Drug | Primary Use | Half-Life (Approx.) | Common Brand Names | Regulatory Class (India) |
|---|---|---|---|---|
| Zolpidem (Stillnox) | Sleep onset insomnia | 2–3 hours | Stillnox, Ambien | Schedule H (Rx-only) |
| Zopiclone (Zop) | Sleep maintenance | 5–6 hours | Zop 7.5, Imovane | Schedule H (Rx-only) |
| Eszopiclone (Hypnite) | Both onset and maintenance | 6–8 hours | Hypnite, Lunesta (Intl.) | Schedule H (Rx-only) |
Can Indian Sleep Medications Be Used in Hong Kong?
While the active ingredients in Indian brands like Zop 7.5 or Hypnite are pharmacologically equivalent to registered hypnotics, their specific formulations may not be registered in Hong Kong.
According to the Drug Office’s Pharmaceutical Product Database, any imported medication must carry a valid Hong Kong registration number (HK-xxxxx) to be legally supplied (Drug Office – Search Drug Database).
Unregistered foreign products — even if identical in composition — are treated as unregistered medicines and cannot be sold or possessed for distribution without a licence.
Practical and Ethical Considerations
In clinical settings, physicians often observe that patients seek overseas alternatives due to cost or accessibility. However, switching formulations or using imported hypnotics without proper supervision can be risky:
- Variations in bioavailability may affect onset time and potency.
- Differences in tablet excipients can alter tolerance or metabolism.
- Lack of official registration means no local pharmacovigilance data or post-marketing surveillance.
Therefore, the recommended approach is to consult a registered Hong Kong doctor for an appropriate, legally approved prescription.
Safe Use Recommendations
- Short-term use only — ideally under two weeks.
- Avoid alcohol or sedating antihistamines while taking hypnotics.
- Do not drive or operate machinery for several hours after ingestion.
- Follow physician tapering advice to prevent rebound insomnia.
- Discuss alternatives such as cognitive behavioural therapy for insomnia (CBT-I), which the WHO and NHS recommend as first-line treatment.
Conclusion
While Stillnox (zolpidem) remains a legally prescribed medication for short-term insomnia in Hong Kong, similar agents such as zopiclone, eszopiclone (Hypnite), and Zop 7.5 mg are commonly prescribed in India under comparable medical frameworks.
However, importing or using foreign versions in Hong Kong without registration is not legally permitted.
For those struggling with chronic insomnia, the safest route is professional evaluation, lifestyle modification, and — if necessary — a locally prescribed hypnotic under medical supervision.