On a Weight-Loss Injection? The Throat, Reflux and Thyroid Questions Malaysians Should Ask Their Doctor

A 44-year-old marketing manager from Bangsar South sat in my clinic last month. She was holding a phone screenshot of her weekly injection schedule. Over six months she had lost 14 kilograms, and she was delighted. She had not come to talk about her weight, though. She came because of a dry cough that woke her at 3am, a sour taste in the morning, and a voice that sounded “tired” by the end of every video call. Her family doctor had treated her for a throat infection twice. The second course of antibiotics did nothing.

When I asked her to list all her medicines, she named her vitamins and her antihistamine. She only mentioned the weekly weight-loss pen when I asked about it directly. She said, “I didn’t think it counted. It’s for my weight, not my throat.”

It counts. (This scenario combines several patients, with details changed to protect privacy. The pattern behind it is one I now see every week.)

GLP-1 medicines, including semaglutide (available as a weekly injection or a daily tablet) and the dual-action injection tirzepatide, have moved from specialist diabetes clinics into everyday Malaysian conversation. They can change lives. But the way they work affects the parts of the body an ENT surgeon looks after: the throat, the voice box, the airway during anaesthesia and, arguably, the thyroid. This article covers the questions I think every Malaysian on one of these medicines should ask, and when to bring them to an ENT specialist.

Why This Matters in Malaysia Right Now

Malaysia has a weight problem that these medicines are designed to address. According to the National Health and Morbidity Survey 2023, 54.4% of Malaysian adults are overweight or obese, up from 44.5% in 2011. When a higher-dose semaglutide injection made specifically for weight management launched in Malaysia in January 2026, it entered a market that was already eager for it.

Demand has kept rising since then. In August 2026, The Star reported that pharmacists were seeing growing demand for weight-loss drugs. The same report described an online market for unapproved slimming injections sold through social media. In July, the National Pharmaceutical Regulatory Agency (NPRA) issued a safety alert on the risk of severe acute pancreatitis with this drug class. NPRA said it had received 504 reports containing 1,066 suspected adverse events, and that 40 products in this class are registered in Malaysia (CodeBlue summary). Then, on 28 August 2026, the Ministry of Health warned the public against “weight-loss pens” claiming to contain retatrutide, an experimental drug that is not approved anywhere in the world.

ENT surgeons are paying attention internationally too. The American Academy of Otolaryngology–Head and Neck Surgery Foundation’s 2026 Annual Meeting (17 to 20 October, Los Angeles) lists “the GLP-1 era” among its six research priorities. Its studies cover thyroid cancer risk, obesity-related airway disease, surgical outcomes and patient counselling.

Put simply, these medicines are now common in Malaysia, and many patients do not think of them as “real” medication when a doctor asks. That gap is what I want to close.

How These Medicines Work, and Why an ENT Cares

GLP-1 is a natural gut hormone. The medicines copy it, and in doing so they reduce appetite, help the pancreas release insulin, and slow down how quickly the stomach empties. That slower emptying is a big part of why people feel full for longer, and it is also the root of most of what follows in this article.

If food stays in the stomach longer, there is more chance that stomach contents travel back up. Some of it can reach the throat and voice box. During an anaesthetic, it can reach the lungs. Nausea and vomiting are the most commonly reported side effects in Malaysia: in the NPRA data, nausea accounted for 183 reports and vomiting for 111. Repeated vomiting also irritates the throat directly.

Question 1: “Could My Weight-Loss Jab Be Causing My Heartburn, Cough or Hoarse Voice?”

It might be. Several large studies have now linked GLP-1 medicines to a higher risk of gastro-oesophageal reflux disease (GERD):

• A 2024 study in Gut, covering about 1.5 million adults with type 2 diabetes, found that people who started shorter-acting GLP-1 medicines had about a 15% higher risk of GERD and its complications than similar patients who did not.
• A 2025 UK study in the Annals of Internal Medicine (summary from the American Gastroenterological Association) compared GLP-1 users with patients on another diabetes drug class. The GLP-1 group had a persistently higher risk of GERD for up to three years.

A caution: these studies looked at classic heartburn-type reflux in people with diabetes. Good studies focused specifically on laryngopharyngeal reflux, the “silent reflux” that affects the throat and voice box, do not exist yet. My concern is based on how the drugs work and on what I see in clinic, not on a published trial. Readers should know which is which.

Silent reflux often does not feel like heartburn. Patients describe:

• A dry, nagging cough, especially after lying down or at night
• Frequent throat clearing and a sensation of mucus stuck in the throat
• A hoarse or “tired” voice by the evening
• A persistent lump-in-the-throat feeling (globus)
• A sour or bitter taste on waking

A Malaysian lifestyle can add to this. A large dinner after a late shift, a sweet milky drink at a 24-hour restaurant, then bed within the hour is already a recipe for reflux. Add a medicine that keeps the stomach full for longer and the effect can stack up. I explain the mechanics in my earlier post on late-night eating and silent reflux. If the lump-in-the-throat feeling is your main symptom, my guide to the constant “lump in your throat” covers it in more detail.

What you can do

• Tell every doctor you see that you are on a GLP-1 or tirzepatide injection, including your GP, your dentist and your specialist.
• Eat smaller portions and stop eating at least three hours before bed. These medicines reward small meals.
• Raise the head of your bed a little if night-time cough is your main symptom.
• Ask your prescriber about dose timing and titration if symptoms began or worsened after a dose increase. Do not stop or change the dose yourself.
• See an ENT specialist if hoarseness lasts more than three weeks, which is a standing rule whether or not you are on these medicines. A simple camera examination in clinic (nasoendoscopy) lets us see the voice box and look for reflux changes or anything more serious. My article on voice problems and hoarseness explains what that visit involves.

Question 2: “I’m Having Surgery or a Scope. Do I Need to Stop My Injection?”

This is the most important safety question in this article, and the one patients most often forget to raise.

Before a general anaesthetic or sedation, we ask you to fast so that your stomach is empty. Once you are asleep, the normal reflexes that protect your airway switch off. Anything still in the stomach can travel up and be breathed into the lungs. This is called aspiration, and it can cause serious pneumonia. Because GLP-1 medicines slow stomach emptying, a patient who has fasted for the usual eight hours may still have food in their stomach.

International guidance has changed as more evidence has come in. In 2023, the American Society of Anesthesiologists suggested holding weekly injections for a week before elective surgery. A 2024 joint guidance from five societies, covering anaesthesia, gastroenterology, bariatric surgery and endoscopic surgery, now says that most patients can continue their medicine. It recommends that those at higher risk follow a liquid-only diet for 24 hours before the procedure. Higher risk includes people in the early dose-escalation phase, people on higher doses, and people with nausea, vomiting, bloating or abdominal pain. Some teams also use a quick bedside ultrasound of the stomach on the day of surgery. I am not aware of a Malaysia-specific national guideline on this yet, so your surgeon and anaesthetist will apply these principles to your case.

For ENT patients, this applies to common operations such as tonsil and adenoid surgery, nasal and sinus surgery, voice box procedures, thyroid surgery and sleep apnea surgery. Several of these involve the airway itself, so we take it especially seriously.

What you can do

• Tell your surgeon and anaesthetist at the first consultation, not on the morning of surgery. That leaves time to plan a liquid diet or a timing change if needed.
• Bring the pen or the box to your pre-operative visit. The exact drug and dose matter.
• Do not stop on your own. If you have diabetes, stopping suddenly can push your blood sugar up. The decision should be made together with your prescribing doctor.
• Report any nausea, vomiting or bloating in the days before surgery. These may be signs that your stomach is emptying slowly.

A quick in-clinic scope with only a numbing spray usually needs no fasting. Any procedure involving sedation or general anaesthesia does.

Question 3: “Will This Medicine Give Me Thyroid Cancer?”

This question appears constantly in Malaysian Facebook groups and TikTok comment sections, so it is worth giving the full picture.

Where the worry comes from. In laboratory studies, these medicines caused tumours of the thyroid’s C-cells in rats and mice. For that reason, the United States label carries a boxed warning. Rodent thyroid C-cells are far more sensitive to this hormone than human ones, and it is not known whether the effect applies to people at all.

What human data show so far. A 2023 French study reported a possible link, but many experts think it reflected detection bias: people on new medicines get more scans, so more small thyroid cancers are found. In 2023, the European Medicines Agency’s safety committee reviewed the evidence and concluded that it did not support a causal link. The largest study to date, published in The BMJ in 2024, followed about 145,000 GLP-1 users across Denmark, Norway and Sweden for an average of almost four years. It found no meaningful increase in thyroid cancer risk. The authors noted that a small increase could not be ruled out completely.

Where the real caution applies. These medicines are not recommended for anyone with a personal or family history of medullary thyroid cancer or a genetic condition called multiple endocrine neoplasia type 2 (MEN 2). If a parent, sibling or child has had thyroid cancer and you do not know which type, find out before you start.

What you can do

• Share your family history of thyroid cancer with your prescriber before starting.
• Check your neck. If you notice a new lump in the front of your neck, a persistent hoarse voice, or difficulty swallowing, see a doctor promptly, whether or not you are on these medicines. My guide on neck swellingexplains what happens next.
• Do not request a thyroid scan “just in case” if you have no symptoms and no risk factors. Routine screening of everyone on these medicines is not recommended. It tends to find small, harmless nodules that cause worry and extra procedures.

If you have already been treated for thyroid cancer, discuss these medicines with your endocrinologist and surgeon together. My post on thyroid cancer follow-up covers how we monitor patients after treatment.

Question 4: “Will It Cure My Snoring or Sleep Apnea?”

Weight loss can improve snoring and obstructive sleep apnea, and in December 2024 the US FDA approved tirzepatide for moderate-to-severe sleep apnea in adults with obesity. That is real progress. But many Malaysians with sleep apnea are not significantly overweight. In those patients, the jaw shape, the tonsils or the nose may be the main cause, and weight loss will not fix that. I covered this in detail in “Weight-Loss Jabs” for Obstructive Sleep Apnea: Help, Hype, or the Real Deal?. The short version: get a proper sleep assessment before assuming the injection has solved the problem, and do not stop CPAP without a repeat sleep study.

Question 5: “Is What I’m Injecting Actually What It Says on the Pen?”

In Malaysia, semaglutide and tirzepatide are prescription-only medicines. Between January and July 2026, the Ministry of Health’s Pharmacy Enforcement Division received 65 complaints and conducted 30 raids linked to weight-loss products, seizing goods worth RM477,142. In 2026, 209 weight-loss advertisements were removed from e-commerce platforms (Malay Mail).

From an ENT and anaesthesia point of view, an unregistered pen is dangerous for two reasons. First, you cannot know the true dose, so you cannot know how slowly your stomach is emptying before surgery. Second, unregistered products obtained privately do not appear in your medical records. NPRA has specifically reminded doctors to ask about privately obtained GLP-1 use, because it may not show up anywhere else.

• Check that a product is registered using the Product Search function on the NPRA website.
• Verify the FarmaTag hologram using the FarmaChecker feature in the MyUBAT app.
• Be suspicious of any seller who skips a medical assessment, and of “doctor” endorsements in online adverts. Some are AI-generated fakes, as I explained in my post on deepfake doctor adverts.

Red Flags: When to Seek Help Quickly

If you are on a GLP-1 or tirzepatide medicine, seek medical attention promptly for:

• Severe, persistent abdominal pain, especially if it spreads to the back, with or without vomiting. Go to an emergency department, as this may be pancreatitis.
• Repeated vomiting or being unable to keep fluids down
• Food sticking when you swallow, or pain on swallowing
• Hoarseness lasting more than three weeks
• A new lump in the neck
• Choking or coughing fits at night, which can be a sign of reflux reaching the airway

None of this means these medicines are bad. For many Malaysians living with obesity, diabetes or sleep apnea, they are a genuine step forward. They work best, and most safely, when every doctor involved in your care knows you are taking them.

Speak to us About Your Throat, Voice or Upcoming Surgery

If you are on a semaglutide or tirzepatide injection, or a similar medicine, and you have a chronic cough, a hoarse voice, a lump-in-the-throat feeling, a neck swelling, or ENT surgery coming up, we are happy to see you. As an ENT, head and neck, and sleep surgeon at UM Specialist Centre in Kuala Lumpur, we can examine your throat and voice box in clinic. We can also work with your prescribing doctor and anaesthetist so that your treatment and your surgery fit together safely.

[Message us on WhatsApp to arrange a consultation](https://api.whatsapp.com/send/?phone=60106612304&text&type=phone_number&app_absent=0)

You can also read more about our throat services, head and neck services and sleep services.

Frequently Asked Questions

Can weight-loss injections cause a sore throat or chronic cough?

They can contribute to it indirectly. By slowing stomach emptying, they may increase reflux. Large studies link these medicines to a higher risk of GERD, which can cause cough, throat clearing and hoarseness. Nausea and vomiting can also irritate the throat. If your symptoms last more than three weeks, have your throat examined.

Should I stop my weight-loss injection before ENT surgery?

Not on your own. Current international guidance says most patients can continue, but higher-risk patients may need a 24-hour liquid diet before surgery or a change in dose timing. Tell your surgeon and anaesthetist early so they can plan with your prescribing doctor.

Do GLP-1 medicines cause thyroid cancer?

Large human studies, including a 2024 Scandinavian study of about 145,000 users, have not shown a meaningful increase in risk, and the European Medicines Agency found no causal link. They should still be avoided if you or a close relative has had medullary thyroid cancer or MEN 2.

Do I need a thyroid ultrasound before starting semaglutide or tirzepatide?

Not routinely. Screening scans are not recommended for people without symptoms or risk factors. See a doctor if you notice a neck lump, a persistent hoarse voice or difficulty swallowing.

How do I know if my weight-loss pen is genuine in Malaysia?

Get it on prescription from a registered doctor or pharmacy. Check the product on the NPRA website’s Product Search, and verify the FarmaTag hologram with the MyUBAT app. The Ministry of Health has warned that “retatrutide” pens sold online are not registered in Malaysia.

Medical disclaimer

This article is for general education and does not replace a personal medical consultation. Do not start, stop or change any prescription medicine without speaking to the doctor who prescribed it.

Appendix A: Sources and External Links Used

1. NHMS 2023 overweight/obesity figures (CodeBlue)
2. Weight-management semaglutide launch in Malaysia, January 2026 (Malay Mail)
3. “Beware the dangers of weight-loss medication”, 5 August 2026 (The Star)
4. NPRA safety alert: GLP-1 and dual GLP-1/GIP agonists and severe acute pancreatitis, 22 July 2026
5. CodeBlue summary of the NPRA alert, 29 July 2026
6. MOH warning on unregistered retatrutide pens, 28 August 2026 (Malay Mail / Bernama)
7. AAO-HNSF 2026 Annual Meeting preview (Newswise)
8. Multisociety guidance on GLP-1 RAs in the perioperative period, 2024 (Surgery for Obesity and Related Diseases)
9. Pasternak et al., GLP-1 RAs and thyroid cancer risk, The BMJ 2024
10. Liu et al., GLP-1 RAs and GERD, Gut 2024
11. AGA summary of 2025 Annals of Internal Medicine GLP-1 and GERD study
12. FDA approval of tirzepatide for obstructive sleep apnea, December 2024
13. NPRA Product Search