Important: This article is general health information based on published research and Australian regulatory sources. It is not medical advice. Side effects vary substantially between individuals. Always consult an AHPRA-registered doctor about your specific situation. For urgent or serious symptoms, call 000 or attend your nearest emergency department.

If you are considering — or already taking — a treatment prescribed through Australia’s alternative medicine pathway, understanding what side effects are possible helps you make informed decisions and recognise when something needs medical attention. This guide summarises what published clinical research and Australian regulatory bodies have reported, hedged appropriately, and pointed at what to discuss with your prescribing doctor.

About This Article

• Educational only — this is general information, not medical advice tailored to your situation.
• Side effects are individual. Not every patient experiences them, and the profile differs between products and dosages.
• Always discuss with your AHPRA-registered doctor. They have your full medical picture; this article does not.
• Sources — TGA (Therapeutic Goods Administration), NHMRC (National Health and Medical Research Council), Cochrane systematic reviews, and peer-reviewed Australian and international clinical literature.
• Last reviewed: 2026-04-30 by Dr Matthew Gartrell, Medical Director.

Why Alternative Medicine Treatments Can Have Side Effects

All medications can produce side effects — alternative medicines are no exception. The clinical literature describes a range of possible effects because these treatments act on body systems that are widespread, and their precise effect profile depends on:

• The composition of the specific treatment prescribed
• The dose and how it is titrated
• The route of administration (different routes produce different absorption profiles)
• Individual factors — age, weight, liver function, other medications, mental health history, and a long list of personal variables

Because of this variability, two patients prescribed the same treatment can have very different experiences. This is one of the reasons your doctor will typically take a “start low, go slow” approach and review you regularly.

Commonly Reported Side Effects in Research Literature

The following effects appear most frequently in published clinical trials and post-market observation studies. None of these are guaranteed to occur in any individual patient, and most are mild and transient where they do occur.

• Drowsiness or fatigue. Frequently reported, particularly during initiation. Usually settles as the body adjusts; sometimes persists and warrants a dose review with the prescribing doctor.
• Dry mouth. Commonly reported. Generally manageable with hydration and oral hygiene.
• Dizziness or light-headedness. Particularly common during the first weeks of treatment. Patients are usually advised to avoid sudden changes of position until the response is understood.
• Changes in appetite. Increased or decreased — varies between patients and treatment compositions.
• Cognitive effects. Short-term effects on memory and concentration are reported in the literature, particularly with treatments containing certain active compounds. The effect is typically dose-related.
• Mood changes. Most patients report no mood change; some report a lift, others report low mood, occasional reports of anxiety. Discuss any noticeable change with your doctor.
• Gastrointestinal effects. Nausea, diarrhoea, or constipation, depending on the formulation and individual response.
• Headache. Reported in a minority of patients, often during initiation.

The TGA, NHMRC, and Cochrane reviews continue to update guidance as new evidence is published. Severity and frequency reported in studies should not be confused with what you personally will experience — this is a guide to what is on the radar, not a forecast of your individual response.

Less Common but Important to Know

These effects are reported less frequently in the literature but are clinically important enough to discuss with your doctor before treatment, and to watch for once you have started.

• Anxiety or paranoia. More commonly reported with treatments containing certain active compounds at higher doses.
• Tachycardia (raised heart rate). Reported in some patients; usually mild but worth raising at consultation if you have a cardiovascular history.
• Liver enzyme changes. Some clinical literature has flagged transient liver enzyme changes; your doctor may request blood tests as a precaution.
• Drug interactions. Particularly with sedatives, blood thinners, antidepressants, and anti-epileptic medications. See the dedicated section below.
• Tolerance and dependence. Under research; the picture differs between recreational and medical patient populations. Discuss with your doctor.
• Hyperemesis syndrome. Rare; reported predominantly in heavy long-term recreational users, a different population from medical patients receiving titrated treatment.

This list is not exhaustive. Any unexpected or significant change after starting treatment should prompt a conversation with your prescribing doctor.

Special Populations

Certain groups need extra care when alternative medicine is being considered. These populations are typically discussed at consultation in more detail than this article can cover:

• Pregnancy and breastfeeding. Generally not recommended; consult your doctor.
• Adolescents and young adults under 25. Brain-development considerations weigh in clinical decision-making for this group.
• Older adults. Falls risk and drug-interaction risk are higher; doses and follow-up cadence are usually adjusted accordingly.
• People with a mental health history, particularly schizophrenia, psychosis, or bipolar disorder. Discussion of risk versus benefit is essential before treatment.
• People with cardiovascular disease. Heart-rate effects warrant careful discussion with the prescribing doctor and your cardiologist if applicable.
• Drivers and machinery operators. See the next section.

Driving and Operating Machinery

Some alternative medicine treatments can impair driving even at therapeutic doses. Australian roadside drug-testing laws are presence-based in most states — meaning a positive test can occur regardless of whether the substance was taken on medical advice and regardless of impairment.

• A valid prescription does not exempt a patient from a positive roadside test.
• The specific impairment effect depends on the treatment, dose, and individual response.
• Always raise driving with your AHPRA-registered doctor before committing to a treatment plan.

For state-specific information, see our state guides:

• Sydney and NSW — presence-based testing, refer to Transport for NSW
• Melbourne and Victoria — presence-based testing, refer to VicRoads
• Brisbane and Queensland — zero-tolerance framework, refer to QLD Department of Transport and Main Roads

This is general information, not legal advice. For current rules and penalties, refer to your state’s road authority.

Drug Interactions to Discuss With Your Doctor

The single most important thing you can do at consultation is disclose every medication, supplement, and over-the-counter product you are taking. Categories that frequently warrant interaction screening include:

• Sedatives and benzodiazepines (e.g. diazepam, lorazepam, temazepam)
• Opioids (e.g. codeine, oxycodone, tramadol)
• Blood thinners (e.g. warfarin)
• Antidepressants (SSRIs and SNRIs, including those used for PTSD and anxiety)
• Anti-epileptic medications
• Some antifungals and antibiotics that affect liver enzymes
• Sleep medications

Most interactions are manageable when the prescribing doctor has the full picture — but they cannot be assessed against information that has not been disclosed. Bring a complete list to your consultation, including supplements and herbal preparations.

How Doctors Reduce Side Effect Risk

Mitigating the risk of side effects is a core part of how AHPRA-registered doctors prescribe. The general approach includes:

• “Start low, go slow.” Beginning at a low dose and titrating up gradually allows the body to adjust and any side effects to surface at low intensity rather than at full dose.
• Composition matched to the patient. Different treatment compositions produce different effect profiles; the doctor selects based on the patient’s individual situation.
• Regular follow-up consultations. A 4–8-week follow-up cadence is common during initiation, with reviews adjusted based on how things are going.
• Patient self-monitoring. A short journal — time of day, what you did, what you noticed — gives the doctor real data at follow-up.
• Adjustment, not stoicism. If side effects outweigh the benefits, doses are adjusted, formulations are changed, or treatment is discontinued. Persisting through significant side effects is rarely the right call.

Follow-up renewal consultations at MyLeaf are $39 AUD — see our pricing page for the full breakdown.

When to Contact a Doctor

If you experience any of the following after starting treatment, contact your doctor:

• New symptoms that were not present before starting treatment
• Worsening of existing symptoms
• Significant changes in mood, sleep, appetite, or cognition
• Cardiovascular symptoms (chest pain, palpitations, breathlessness)
• Severe nausea or persistent vomiting
• Any reaction that concerns you, even if you are not sure it is related

For urgent or serious symptoms, call 000 or attend your nearest emergency department. Telehealth and patient-portal messaging are not appropriate for emergencies.

For non-urgent concerns, contact MyLeaf on 1800 695 323 (Option 3 for Clinical Team), Monday to Friday 9am–5pm AEST. For more on what to do after a consultation, see What to Expect After Your First Telehealth Consultation.

Reporting Side Effects to the TGA

Patients and clinicians can report adverse events directly to the Therapeutic Goods Administration. This contributes to ongoing safety monitoring and is encouraged for any unexpected or serious reaction.

• TGA Adverse Event Reporting: tga.gov.au/reporting-problems
• By phone: 1800 044 114 (TGA reporting line)

Reporting is anonymous if you prefer. You do not need to be certain a side effect was caused by your treatment — the TGA encourages reports of any unexpected reaction so patterns can be identified across the patient population.

What to Tell Your Doctor at Follow-Up

A productive follow-up consultation depends on what you bring to it. Useful information includes:

• All symptoms — even ones you are unsure are related to the treatment.
• Time of day they typically occur.
• Whether they happen at every dose or only some — and if some, what was different about those doses.
• Other medications, supplements, alcohol, or recreational substances — full disclosure is critical, even if you think something might be unflattering. Your doctor cannot assess interactions against information they do not have.
• Lifestyle factors — sleep, stress, diet, exercise, recent travel, recent illness.

Write notes throughout the period between consultations — even short ones. Memory is unreliable about timing and patterns; written notes are not.

Frequently Asked Questions

Are side effects worse with one type of active compound or another?
Different active compounds in alternative medicine treatments have different side-effect profiles. Cognitive effects and anxiety are more commonly reported with some compositions; sedation and gastrointestinal effects with others. Your doctor will discuss this in the context of what you are prescribed.

Will side effects go away over time?
Many of the commonly reported side effects (drowsiness, dry mouth, mild dizziness) settle within the first 1–2 weeks as the body adjusts. Some persist and warrant a dose review. Some are not dose-related and may require a change of formulation or treatment. Your follow-up consultation is where this gets sorted.

Can I drink alcohol while taking alternative medicine?
Alcohol can amplify drowsiness and cognitive effects, and may interact with the metabolism of some treatments. Discuss your alcohol consumption honestly at consultation — your doctor will give you specific guidance for your situation.

Is it safe to combine with my regular prescription medications?
This is exactly what your prescribing doctor needs to assess at consultation, with your full medication list in front of them. Most interactions are manageable when the doctor has full information. Never combine medications without disclosing them all to your treating doctor.

What’s the difference between a side effect and an allergic reaction?
Side effects are generally predictable based on what the treatment does — drowsiness, dry mouth, gastrointestinal upset. Allergic reactions are typically immune-mediated and present differently — rash, itching, swelling, breathing difficulty. A reaction involving breathing difficulty, throat tightness, or facial swelling is a medical emergency — call 000 immediately. Any rash or unusual itching after starting a new treatment should be discussed with your doctor.

For more general questions, see the full FAQ.

References

• TGA — Medicinal Cannabis Hub: tga.gov.au/medicinal-cannabis-hub (regulatory framework, adverse-event reporting, prescribing information for clinicians)
• NHMRC — National Health and Medical Research Council: nhmrc.gov.au (clinical guidance and research summaries)
• Cochrane Library: cochranelibrary.com (systematic reviews of alternative medicine in adult populations)
• Australian Government Department of Health and Aged Care: health.gov.au
• Phoenix Australia (mental health context): phoenixaustralia.org
• Black Dog Institute (mood and anxiety): blackdoginstitute.org.au

This article cites Australian regulatory sources and peer-reviewed clinical literature available at the time of last review. As clinical evidence evolves, this page is reviewed periodically by the MyLeaf Medical Team.

Next Steps

Side effects are individual, doctors aim to minimise them through careful prescribing and follow-up, and reporting unexpected effects helps the whole patient population. If you are worried about something specific to your treatment, the right next step is a conversation with your prescribing doctor — not the internet.

Book a follow-up consultation at $39, or an initial consultation at $49 if you are new. See our pricing page for the full breakdown.

Mental health and crisis support: Lifeline 13 11 14, Beyond Blue 1300 22 4636, Open Arms (veterans) 1800 011 046. In an emergency, call 000.

This article is general health information based on published research and Australian regulatory sources. It is not medical advice. Side effects vary substantially between individuals. Always consult an AHPRA-registered doctor about your specific situation.

Last medically reviewed: 2026-04-30 by Dr Matthew Gartrell, Medical Director, MyLeaf. ABN 80 655 715 834.

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