Tirzepatide: what it is and which brand it is sold under in Spain

What is tirzepatide and how does it work?

Tirzepatide activates the receptors of two gut hormones: glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) [2]. Both are involved in the body’s response to food. Their action helps release insulin when blood glucose rises and may reduce appetite [2].

Semaglutide acts on the GLP-1 receptor [3], while tirzepatide acts on GLP-1 and GIP [2]. This difference in mechanism is not enough to choose a treatment. The reason it was prescribed, other health conditions, the medicines you take and how well you tolerate it also matter. In our comparison of Ozempic, Wegovy and Mounjaro, we distinguish between molecules, indications and formulations.

A stronger feeling of fullness may change how much you feel like eating. It can also make your usual meals feel too large. That is why, in consultations, we ask about appetite, digestive symptoms and the meals you are actually able to manage. A helpful eating plan leaves room for protein, plant foods, fluids and the enjoyment of eating.

Our guide to GLP-1 medicines places tirzepatide within this family. It explains which questions may be useful to take to your medical appointment and how nutritional support can help.

Which brand is it sold under, and what is it authorised for?

In Spain, tirzepatide is sold as Mounjaro, as a once-weekly injection available on prescription [1]. It has two authorised indications [1]. The first is inadequately controlled type 2 diabetes, in adults and from the age of 10. The second is weight management in adults, alongside a reduced-calorie diet and increased physical activity.

For weight management, the product information specifies a body mass index of 30 or above, or 27 to 30 with at least one weight-related condition [1]. These criteria guide the indication but do not replace an individual assessment. Our Mounjaro information page brings together details about the medicine.

Dose escalation starts at 2.5 mg once a week for four weeks, followed by 5 mg [1]. If a higher dose is needed, it is increased in 2.5 mg steps, with at least four weeks at each dose and a maximum of 15 mg in adults [1]. Your doctor decides whether to increase or maintain the dose, or review the treatment plan.

Nausea, diarrhoea and vomiting are more common when the dose is increased and usually lessen over time [1]. If they occur, tell the person who prescribed it. You do not need to put up with them in silence or stop eating on your own. Your doctor adjusts the medicine; in consultations, we adapt how meals are organised.

Tirzepatide delays stomach emptying, and the product information recommends monitoring oral medicines with a narrow therapeutic index, such as warfarin or digoxin, particularly when starting treatment and increasing the dose [1]. The Spanish product information does not call for an adjustment to the dose of oral contraceptives, although it recommends that women of childbearing potential use contraception during treatment [1]. Always discuss this with the person who prescribed it.

Is tirzepatide publicly funded in Spain?

No. Public funding does not cover Mounjaro for any of its indications, and the Spanish Ministry of Health lists it as “Not funded by resolution” [4]. In December 2025, the Interministerial Commission on Medicine Prices agreed not to include its six presentations in the benefits covered by the National Health System [5].

Having a prescription does not mean that the public health system pays for the medicine. Under the current situation, you pay the full cost at the pharmacy, including if you have type 2 diabetes. The price varies according to the pack strength; the table range is indicative because we have not been able to verify it by national code in a publicly available official source, so it is best to confirm it with your pharmacy.

Understanding the molecule can help you ask better questions; the indication and dose are decided during your medical assessment.

What do tirzepatide trials show?

Trials report averages for specific groups, with a set follow-up period and lifestyle changes. Their figures help explain potential benefits and limitations, but they cannot predict your result. When reading each percentage, the duration, study population and dose all matter.

The SURMOUNT-1 trial included adults with obesity, or with overweight and a related complication, who did not have diabetes [6]. At 72 weeks, mean weight loss was 15.0%, 19.5% and 20.9% with 5, 10 and 15 mg, respectively [6]. The placebo group lost 3.1%. All groups received support to change their habits [6].

This is an average effect in that population. It does not allow anyone to promise the highest percentage to an individual. If you have type 2 diabetes, your medical goals also include blood glucose management.

SURMOUNT-5 directly compared tirzepatide and semaglutide in adults with obesity, or with overweight and a related complication, who did not have diabetes [7]. At 72 weeks, mean weight reduction was 20.2% and 13.7%, respectively [7]. Each group used the highest dose they could tolerate, and participants knew which medicine they were receiving. The result describes groups; it does not say which option is right for a particular person.

Weight is not the whole picture. Some of the weight lost is lean mass, which includes muscle, water and other tissues. Eating enough protein and doing strength exercise help protect muscle during treatment [8].

Is there a generic version of tirzepatide?

For now, tirzepatide is sold in Spain as Mounjaro, which is not a generic medicine [4]. A generic can only become available once patent protection expires and it is also authorised and marketed. So a patent date alone does not tell you when one will be available at the pharmacy.

If you see adverts promising cheaper tirzepatide or offering it without a prescription, be cautious and ask your pharmacist. Do not replace your prescribed medicine with an offer whose source and storage conditions you cannot verify. We explain this in our guide to the risks of buying these medicines without a prescription.

What to eat while using tirzepatide

When you have less appetite, it helps to focus on the quality of what you do eat. A joint document from four scientific societies prioritises adequate protein, good-quality foods and physical activity during treatment [8]. A small meal can include a protein food, a plant food and a source of energy. For example, an omelette with bread and tomato, or a dish of pulses with vegetables and rice.

If a large meal feels difficult, try smaller portions spread across the day. Keep fluids within reach and notice how well you tolerate them. If symptoms stop you eating or drinking normally, tell the person who prescribed the medicine. A sample weekly menu during GLP-1 treatment can give you ideas for planning your meals.

What we see in consultations

The question we hear most often in consultations is whether simply eating less is enough to look after your health. We see weeks when appetite falls so much that people skip whole meals. We then look at which foods provide protein, how meals are spaced and whether strength activity is maintained. Our guide to protein and muscle with GLP-1 covers this in more detail.

We also hear questions about how long the medicine will need to be continued. That is a medical decision. We can work with you on sustainable habits and an eating plan that still makes sense if your treatment changes. The conversation includes routines, shopping, hunger, fullness and social life, and goes beyond the number on the scales.

If you have or have had an eating disorder, tell your doctor before starting. At Alimmenta, we provide support alongside the psychology team.

Your first step this week

Notice one meal. Make a note of whether your reduced appetite is leaving out a source of protein, and mention it at your next appointment.

If you already have a prescription and need to adapt your meals, find out about our GLP-1 nutrition support service. We do not prescribe or change your dose.