Answer the side-effect intent for cyproheptadine without diagnosing; distinguish common from serious reactions and give safe next-step/reporting guidance.
Source
Clinical statements on this page are taken from the SAHPRA-approved patient information leaflet (approved 06/02/2024) and professional information (approved 06/02/2024) for this product: patient information leaflet, professional information. Retrieved 2026-09-03. Where this page and the approved leaflet differ, the leaflet is correct.
What is cyproheptadine?
Which leaflet this comes from
There is no approved leaflet for Cyproheptadine in SAHPRA’s public repository. The information below is from the approved leaflet for ZYACTIN, another South African product containing Cyproheptadine. Products with the same active ingredient can still differ in strength, formulation and approved uses, so check the leaflet in your own pack.
Cyproheptadine contains the active ingredient Cyproheptadine.
- Active ingredient — Cyproheptadine
- Registration number — 55/5.7.1/0847
- Registration holder — Zydus Healthcare SA (Pty) Ltd
It is approved for:
- ZYACTIN contains cyproheptadine which belongs to a group of medicines known as sedating antihistamines
- It is used to relieve allergies, such as hay fever and some allergic skin conditions
Common side effects of cyproheptadine
Not everyone gets side effects. The effects below are those listed in the South African approved leaflet, grouped using the leaflet’s own frequency wording.
About these frequency terms
This leaflet groups effects as “Frequent” and “Less frequent” rather than the very common/common/uncommon scale used in some other markets.
Frequent side effects
- sleepiness or drowsiness (the drowsiness side effect might get less after 3 to 4 days of use)
Less frequent side effects
- feeling sedated, restless or confused
- feeling excited, exaggerated or uncontrollable emotion
- nervousness, irritability, aggressive behaviour
- anaemia (fatigue, loss of energy, pale skin, cramps in your legs, difficulty with concentration)
- increased appetite or weight gain
- headaches or dizziness
- coordination problems
- tremors (involuntary trembling or shaking of hands and feet)
- tingling or numbness of your hands and feet (pins and needles)
- difficulty falling or staying asleep
- unrealistic feeling of well-being
- seeing or hearing things that do not exist (hallucinations)
- vertigo (sensation of spinning or swaying)
- blurred vision or double vision
- ringing in your ears (tinnitus)
- sensation of rotation or movement
- low blood pressure
- coughing up thick mucus, chest tightness or wheezing
- blocked nose, nose bleeds
- dry mouth, nose or throat, upper abdominal pain or discomfort, nausea (feeling sick), vomiting (being sick), diarrhoea, constipation
- loss of appetite (anorexia)
- abnormal liver function
- increased sensitivity of your skin to the sun
- urticaria (swelling, redness and itchiness of the skin)
- increased sweating
- early start of a women’s period
- feeling tired
- sudden feeling of coldness with shivering (chills) accompanied by a rise in your body temperature (rigors)
Frequency unknown side effects
- diminished mental alertness, confusion
- hallucinations (seeing or hearing things that are not real)
- restlessness
- excitation
- aggressive behaviour
- euphoria (a feeling of intense excitement and happiness)
Serious side effects and warning signs
This leaflet does not set out a separate list of serious side effects. The general warning signs below apply to any medicine.
General warning signs that apply to any medicine
Call for emergency help now if any of these happen
- Difficulty breathing, wheezing, or tightness in the throat or chest
- Swelling of the face, lips, tongue or throat
- A widespread rash with blistering or peeling skin, or sores in the mouth, eyes or genitals
- Fainting, collapse, or a sudden severe drop in alertness
- Chest pain, or sudden weakness or numbness on one side of the body
- A fit (seizure), or confusion that comes on suddenly
In South Africa call 10177 for an ambulance, or 112 from a mobile phone. Go to your nearest emergency department if it is faster. Do not wait to see whether the symptom settles.
How long can side effects last?
How long a side effect lasts depends on the effect, the product, how long it has been used, and the person. Some effects ease within days as the body adjusts. Others continue for as long as the product is used. A few can persist after stopping, and some need review rather than waiting.
- Settling effects — mild effects that ease over the first days or weeks of use
- Ongoing effects — effects that continue while the product is being used and improve after stopping
- Persistent effects — effects that continue after stopping and need medical review
- Delayed effects — effects that appear after weeks or months rather than immediately
Which of these applies to a particular effect is a clinical question. If a side effect is not settling, is getting worse, or is affecting your daily life, that is worth a conversation with a pharmacist or doctor regardless of how long it has been going on.
Evidence required before publish — source the following for cyproheptadine from the SAHPRA-approved patient information leaflet or professional information, and cite what you actually used.
- Anything the approved information for cyproheptadine says about how long specific effects last
- Whether the source describes any effect as usually temporary, or as needing review if it persists
- Whether any effect is described as continuing after the product is stopped
Factors that may affect side effects
The approved leaflet identifies the following cautions and factors.
Do not use it at all if
- If you or your child is hypersensitive (allergic) to cyproheptadine or any of the other ingredients of ZYACTIN
- If you or your child has a condition which causes increased pressure in your eyes, such as glaucoma
- If you have prostate problems, or if you have been experiencing any difficulty passing urine
- If you or your child is taking medicines called monoamine oxidase inhibitors (MAOIs)
- If you know you or your child has a stomach ulcer or a blockage in your small intestines
- If you are an elderly adult or very weak
- If you are a nursing mother
Use with care, and tell your doctor, if
- If you or your child experiences dizziness, drowsiness or low blood pressure. This can be because of ZYACTIN treatment
- If you or your child suffers from asthma, an underactive thyroid, high blood pressure, heart disease or respiratory disease. If you or your child is scheduled for blood or urine testing, ask your doctor if you should stop taking or giving ZYACTIN for several days before testing. ZYACTIN may affect your test results. ZYACTIN is not meant to treat acute asthma attacks. If an attack occurs, follow the instructions your doctor has given you. Always have your inhaled rescue medicine for asthma attacks with you. Children ZYACTIN should not be given to children under 2 years of age, as the safety and efficacy have not been established
Pregnancy and breastfeeding
- If you are pregnant or breastfeeding, think you may be pregnant or are planning to have a baby, please consult your doctor, pharmacist or other health care provider for advice before taking ZYACTIN
- The safety of ZYACTIN during pregnancy has not been established
- Do not take ZYACTIN if you are breastfeeding
Interactions and medicines to check
The approved leaflet names these interactions.
- Hypnotics, sedatives, tranquillisers (used to treat sleeping disorders or anxiety)
- Antidepressants (used to treat depression). ZYACTIN with food, drink and alcohol Do not take ZYACTIN with alcohol, as the simultaneous intake of alcohol may make you feel drowsier or cause additional reductions in alertness and impairment of performance
Bring the actual products to the conversation
A pharmacist can check for interactions much faster from the packaging than from remembered names.
What to do if you experience side effects
If you think you are having a side effect, the response depends on how severe it is. Use the warning signs above first — if any of those apply, treat it as urgent.
If the symptom is severe or frightening
Get medical help immediately. Call 10177 for an ambulance, or 112 from a mobile phone, or go to the nearest emergency department. Take the product and its packaging with you if you can.
If the symptom is mild but bothering you
- Write down what the symptom is, when it started, and how it relates to when you take the product
- Check the leaflet that came with the product to see whether the symptom is listed
- Speak to your pharmacist — for many questions this is the fastest route to a useful answer
- Contact the prescriber if the symptom is affecting your daily life or is not settling
Do not stop a prescribed treatment on your own
Stopping some treatments suddenly causes its own problems, and the condition being treated may get worse. If you want to stop, ask a pharmacist or doctor how to do it safely — they can usually offer an alternative.
You can also report a suspected side effect in South Africa. Reporting does not replace getting medical advice, and you do not need to be certain the product was the cause.
When to seek urgent medical help
Some symptoms need medical attention straight away rather than an appointment in a few days. Do not wait to see whether they settle.
Call for emergency help now if any of these happen
- Difficulty breathing, wheezing, or tightness in the throat or chest
- Swelling of the face, lips, tongue or throat
- A widespread rash with blistering or peeling skin, or sores in the mouth, eyes or genitals
- Fainting, collapse, or a sudden severe drop in alertness
- Chest pain, or sudden weakness or numbness on one side of the body
- A fit (seizure), or confusion that comes on suddenly
In South Africa call 10177 for an ambulance, or 112 from a mobile phone. Go to your nearest emergency department if it is faster. Do not wait to see whether the symptom settles.
Get same-day medical advice if you have
- A high fever, or a rash together with feeling generally unwell
- Yellowing of the eyes or skin, or unusually dark urine
- Unusual bruising or bleeding that you cannot explain
- Severe or persistent vomiting or diarrhoea, especially if you cannot keep fluids down
- A sudden change in mood, or thoughts of harming yourself
- Any symptom that is rapidly getting worse
If you are having thoughts of harming yourself
Help is available in South Africa. The SADAG helpline is 0800 567 567, or you can go to your nearest emergency department. You do not have to wait until it feels like an emergency.
How to report a suspected side effect in South Africa
South Africa has an official system for reporting suspected side effects, run by the South African Health Products Regulatory Authority (SAHPRA). Reports from the public and from healthcare professionals are how safety signals get detected after a product is already in use.
Who can report
Anyone can report — you do not have to be a healthcare professional, and you do not need to prove that the product caused the problem. A suspicion is enough. Patients, caregivers and family members can all submit a report.
What to have ready
- The name of the product, its strength and form, and the batch number if you have it
- Why it was being used, and when it was started and stopped
- What the suspected reaction was, when it began, and how long it lasted
- Any other medicines, supplements or remedies being used at the same time
- Basic details about the person affected — age and sex are usually enough
How to report
SAHPRA accepts adverse reaction reports through its e-Services reporting system and through the Med Safety mobile app. Healthcare professionals can also report through the same routes. Current forms and access points are published on the SAHPRA site.
- SAHPRA Health Products Vigilance — the main vigilance and reporting hub
- SAHPRA e-Services — current adverse reaction reporting access
Reporting is not a substitute for medical care
If someone is unwell now, get medical help first and report afterwards. Urgent symptoms always take precedence over paperwork.
For a fuller walkthrough see how to report an adverse drug reaction.
Related pages
← Back to more medicine side effects.
Report a side effect
If you think you have had a side effect, you can report a suspected side effect in South Africa. Report a suspected side effect through the appropriate SAHPRA pathway where relevant.
Information only
This page gives general medicine-safety information for people in South Africa. It is not a diagnosis and not personalised medical advice. It cannot tell you whether a symptom you are having is caused by a particular product. Speak to a pharmacist or doctor about your own situation, and do not stop or change a prescribed treatment on the basis of a web page.
Editorial status: draft — not for publication
Brief SE-00408 · build rank 408 · Phase 2 · Tier 2. Every evidence slot on this page must be completed from the SAHPRA-approved source and the page signed off by a qualified clinical or pharmacy reviewer before it is published. Target length 1,300–2,000 words.