Errors Possible When Microdosing (Counting Clicks) to Dose Weight Loss Medicines

Published January 6, 2025

Over the past few years, the use of glucagon-like peptide-1 (GLP-1) receptor agonist medicines to help people manage their weight and/or diabetes has exploded. The GLP-1 medicines approved for diabetes and weight management include the following:

• semaglutide (Ozempic, Wegovy)
• liraglutide (Victoza, Saxenda)
• tirzepatide (Mounjaro, Zepbound)

The success of these medicines has increased the demand. As a result, many of these products have become hard to get due to the short supply. Trying to find available medicine, both healthcare providers and people using these drugs continue to look for alternate sources to obtain them. This includes compounding pharmacies, weight-loss clinics, the internet, and others. Unfortunately, there have been several reports of errors and adverse events following the use of these compounded medicines.

Most of the GLP-1 medicines are injectable products available in prefilled pen devices. These prefilled pen devices make it easy for people to administer the drug to themselves. For example, you typically twist the end of the pen to line up an arrow with the number that matches the intended dose. Once the arrow is set, the injection can be given.

However, within the past few months, we learned that some healthcare providers are telling people to prepare smaller doses than the dose options labeled on the pen. To get a smaller dose, the person must count a certain number of “clicks” as they turn the knob. This technique is referred to as microdosing or click counting.

Microdosing (or click counting) involves purposefully injecting less medicine than the typical prescribed dose. Some of the reasons microdosing is used include the following:

• Reducing mild (but undesirable) side effects
• Maintaining desired weight loss with a lower dose
• Reducing treatment costs
• Extending the use of a single pen device when the medicine is difficult to obtain or expensive

Wegovy, Mounjaro, and Zepbound pens come in fixed-dose, single-use pens and therefore click counting cannot be used for microdosing. But Ozempic, Victoza, and Saxenda are available in dose-adjustable prefilled pens. The dose-adjustable pen has dose markings for each approved dose. To advance from one dose to the next, the pen dial clicks multiple times. To dial a microdose, people are told to count the clicks made when turning the pen device’s dosing knob instead of dialing the knob to the dose number.

Novo Nordisk, who manufactures liraglutide and semaglutide, does not recommend using click counting to prepare a dose of the medicine. In addition, there are also no studies that support this dosing method. However, there are stories in the media and a number of podcasts about this topic which have raised some concerns about safety.

Microdosing or click counting these medicines can lead to errors. Some of the problems include the following:

• Healthcare providers are writing prescriptions for these medicines using approved doses. However, the healthcare provider is telling the person in the office to dial the pen, by counting the number of clicks, to a dose that is different from what is written on the prescription. This could lead to the following errors:
  • If the person is told to count clicks to dose the medicine, the instructions on the pharmacy label will not match what the person was told to do. This could lead pharmacists to educate patients on the wrong dose and can contribute to subsequent dosing errors.
  • Microdosing and administering a different dose at home can result in wrong dose errors if the person is admitted to the hospital or another healthcare facility. The person may then receive a higher dose, based on the prescription information, leading to adverse effects.

• Dialing and counting to the correct number of clicks may be difficult for someone with hearing loss or mobility issues, such as arthritis or tremors. Also, when counting a high number of clicks (e.g., 36, 54), a person may easily be distracted and miscount. In either scenario, the wrong dose maybe administered.
• If microdosing, pens may last longer than the pharmacy team expected. Therefore, people may not have enough pen needles to last beyond the expected days’ supply. They may be tempted to reuse pen needles, which is an unsafe practice.
  • For example, an Ozempic pen should only be used for 56 days after administering the first dose. If people are microdosing with this pen, there is the risk that they may be using it for more than 56 days (and may not have enough new pen needles for each microdose).

Here’s what you can do: While the use of microdosing or click counting is controversial, this practice may be more widespread than originally thought. Consider the following recommendations to prevent dose-related errors with microdosing of GLP-1 medicines:

• Ensure you or your caregiver can count the prescribed number of clicks accurately and consistently.
• Make sure you have clear verbal and written instructions for the microdose your healthcare provider wants you to take.
• Ask your healthcare provider to document the microdose and the prescribed number of clicks in your medical record.
• Ensure your pharmacist knows the prescribed microdose and the number of clicks the healthcare provider instructed you to take.
• Keep (and share) an up-to-date list of your medicines, including the doses (number of clicks) you are actually taking.
• Speak up about any concerns you have about your ability to count the required number of clicks.

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