Medical cannabis in Spain: new 2025 regulation
Medical cannabis in Spain now has specific regulation thanks to Royal Decree 903/2025, a rule that establishes how standardized cannabis preparations must be prescribed, prepared and dispensed within the hospital setting.
From the Hydroponics Blanes blog, we want to explain this new development in a clear, approachable and responsible way. This article is for informational purposes only. We do not sell marijuana with THC. In our online store, you can find technical products for self-cultivation, such as fertilizers, nutrients, lighting systems for indoor cultivation, grow tents, ventilation, meters, substrates, hydroponic systems and accessories to improve crop control.
What is Royal Decree 903/2025 on medical cannabis?
Royal Decree 903/2025 regulates the conditions for the prescription, preparation, dispensing and use of standardized cannabis preparation magistral formulas. In other words, it allows certain cannabis-derived preparations to be used for therapeutic purposes, but always within a medical, controlled and hospital-based framework.
This regulation does not mean that cannabis with THC can be sold freely. The regulation is designed for specific patients, with specific conditions and under the criteria of specialist doctors. The main objective is to offer a therapeutic alternative when other authorized treatments have not worked properly or have caused tolerance problems.
The decree also aims to guarantee quality, traceability and safety. For this reason, the preparations must have a controlled composition, be registered and be prepared using authorized pharmaceutical procedures.
Main points of medical cannabis regulation in Spain
The new regulation introduces several important points that should be understood in order to avoid confusion. Regulated medical cannabis should not be confused with recreational use or with commercial products without pharmaceutical control.
Prescription only by specialist doctors
One of the key points of Royal Decree 903/2025 is that magistral formulas with standardized cannabis preparations can only be prescribed by specialist doctors. The prescription must be made in a clinical context and with documented medical justification.
This means that it is not a product that can be purchased directly in any establishment. Access remains reserved for patients evaluated within the healthcare system and with professional monitoring.
Preparation in hospital pharmacies
Medical cannabis preparations must be prepared and dispensed in hospital pharmacy services. This point is essential because it allows the formula, dosage, quality of the preparation and full traceability of the treatment to be controlled.
In medical treatment, the composition must be precise. For this reason, standardized preparations must indicate controlled levels of cannabinoids such as THC and CBD, as well as comply with technical requirements established by health regulations.
Registry managed by the AEMPS
The AEMPS, Spanish Agency for Medicines and Health Products, manages the registry of standardized cannabis preparations. This registry makes it possible to identify which preparations can be used for the preparation of standardized magistral formulas.
The objective of this registry is to strengthen safety, control the quality of the products used and guarantee adequate traceability from the initial preparation to the final dispensing to the patient.
For which illnesses is medical cannabis considered?
Medical cannabis in Spain is considered for specific clinical situations, especially when usual treatments do not provide a sufficient response. Among the most important initial indications are the following:
- Refractory chronic pain: persistent pain that does not improve adequately with conventional treatments.
- Spasticity associated with multiple sclerosis: muscle stiffness, spasms and functional limitation in certain patients.
- Refractory epilepsy: forms of epilepsy that do not respond well to usual medications.
- Chemotherapy-induced nausea and vomiting: side effects that may appear during oncological treatments.
The regulation allows these indications to be expanded in the future if new scientific evidence emerges and if the AEMPS publishes new monographs in the National Formulary. Therefore, the legal framework begins with a cautious approach, but also with the capacity to adapt.
Difference between THC and CBD in medical cannabis
To understand this regulation, it is important to differentiate between THC and CBD. Both are cannabinoids present in the cannabis plant, but they have different characteristics.
THC is the compound most associated with the psychoactive effect of cannabis. For this reason, preparations with relevant concentrations of THC are subject to strict controls. CBD, on the other hand, does not produce the same psychoactive effect and has attracted interest for possible therapeutic applications in different medical fields.
In the hospital setting, the ratio between THC and CBD must be controlled. The dose, composition and form of administration depend on the medical assessment, the clinical indication and the characteristics of the authorized preparation.
What benefits can CBD provide?
CBD has been the subject of numerous studies for its possible usefulness in different clinical situations. Among the most studied effects are support in certain types of epilepsy, relief of some types of pain, improvement of nausea associated with medical treatments and modulation of inflammatory processes.
Even so, caution is advisable. Not all CBD-based products are the same, not all have authorized therapeutic purposes and not everyone responds in the same way. The difference in the new regulated framework lies in medical control, pharmaceutical preparation and standardized composition.
For this reason, when talking about medical cannabis, it does not refer to freely available products, but to specific preparations used under healthcare supervision and with clinical monitoring.
Quality control and safety of preparations
One of the most important points of Royal Decree 903/2025 is quality control. Standardized cannabis preparations must meet technical criteria that make it possible to know the composition, control the presence of cannabinoids and avoid risks due to contaminants.
Traceability is also essential. Each preparation must be documented in order to know the origin, composition, preparation process and dispensing. This control allows work to be carried out with greater safety and facilitates treatment monitoring.
In addition, the regulation includes pharmacovigilance. This means that healthcare professionals and patients can report possible adverse reactions. In this way, useful information is collected on safety, tolerance and possible unwanted effects.
Can medical cannabis be bought in a grow shop?
No. Regulated medical cannabis under Royal Decree 903/2025 is not sold in grow shops, online stores or conventional businesses. Dispensing is linked to the hospital setting and requires a prescription from specialist doctors.
At Hydroponics Blanes, we do not sell marijuana with THC or medical cannabis preparations. Our activity focuses on products for self-cultivation, technical gardening and indoor cultivation, always within the legal framework.
What products can be found at Hydroponics Blanes?
Although medical cannabis belongs to the healthcare field, many people interested in technical cultivation look for products to improve indoor installations, control environmental parameters and work more precisely. At Hydroponics Blanes, we offer specialized cultivation material and technical advice.
Fertilizers and nutrients for indoor cultivation
Fertilizers for indoor cultivation are essential for providing nitrogen, phosphorus, potassium, calcium, magnesium, iron and other micronutrients necessary for plant development. Balanced nutrition helps prevent deficiencies, lockouts and growth problems.
To obtain good results, it is advisable to combine growth fertilizers, flowering fertilizers, root stimulators, enzymes, pH correctors and EC meters. Each crop requires a nutritional strategy adapted to the system, the substrate and the stage of development.
LED lighting for indoor cultivation
LED lighting for indoor cultivation makes it possible to improve energy efficiency, better control temperature and provide a suitable spectrum for growth and flowering. Choosing the right lamp depends on the available space, the required power, the cultivation surface and the type of plant.
Modern LED equipment allows work with lower heat emission compared to other traditional systems. It also helps maintain a more stable environment and improve energy use.
Hydroponic systems and RDWC
Hydroponic systems allow cultivation without soil using a controlled nutrient solution. In systems such as RDWC, dissolved oxygen, water temperature, pH and EC are key factors for healthy root development.
For this type of cultivation, we recommend using reliable meters, air pumps, air stones, suitable reservoirs, nutrients compatible with hydroponics and cleaning products to keep the circuit in good condition.
Environmental control and ventilation
Environmental control is essential in any indoor installation. Extractors, carbon filters, fans, humidifiers, dehumidifiers and climate controllers make it possible to maintain temperature, humidity and air renewal within suitable ranges.
A well-ventilated room reduces the risks of fungi, heat stress and humidity build-up. It also promotes proper plant transpiration and improves nutrient uptake.
Why this regulation is important
The approval of Royal Decree 903/2025 represents an important step for the therapeutic use of cannabis in Spain. The chosen approach prioritizes safety, medical control, pharmaceutical quality and scientific evidence.
It also helps separate two different realities: on the one hand, medical use under hospital prescription; on the other, the sector of technical cultivation, fertilizers, lighting, hydroponics and products for legal self-cultivation.
This difference is important in order to provide accurate information and avoid confusing messages. Medical cannabis is not a freely sold product, while the cultivation items available at Hydroponics Blanes are aimed at technical gardening, indoor cultivation and self-cultivation within the law.
Frequently asked questions about medical cannabis in Spain
Who can prescribe medical cannabis?
Only specialist doctors can prescribe standardized cannabis preparation magistral formulas within the hospital setting.
Where are the preparations dispensed?
Dispensing is carried out in authorized hospital pharmacy services, with quality control, traceability and clinical monitoring.
Which patients can access the treatment?
Access is intended for patients with specific clinical indications, especially when other treatments have not provided a sufficient response. Initial cases include refractory chronic pain, spasticity due to multiple sclerosis, refractory epilepsy and nausea or vomiting associated with chemotherapy.
Does CBD get you high?
CBD does not produce the same psychoactive effect associated with THC. Even so, when used for therapeutic purposes, it must be assessed within a medical context, especially if the person is taking other medications.
Does Hydroponics Blanes sell medical cannabis?
No. Hydroponics Blanes does not sell marijuana with THC or medical preparations. The store offers products for self-cultivation and indoor cultivation, such as fertilizers, nutrients, LED lighting, hydroponic systems, grow tents, ventilation, meters and technical accessories.
Responsible information from Hydroponics Blanes
Medical cannabis in Spain is entering a new stage, with greater health control and a regulated framework for certain patients. From the Hydroponics Blanes blog, we will continue to share information on cultivation, plant nutrition, lighting, hydroponics, environmental control and relevant news in the sector.
This article is not a medical recommendation. For any health-related doubt, the correct path is to consult healthcare professionals. For questions related to indoor cultivation, fertilization, lighting systems or technical material for self-cultivation, Hydroponics Blanes offers specialized advice and suitable products to work with greater control.
Sources consulted
- Official State Gazette: Royal Decree 903/2025, of October 7, establishing the conditions for the preparation and dispensing of standardized cannabis preparation magistral formulas.
- Spanish Agency for Medicines and Health Products: information on standardized cannabis preparations and the registration procedure in the corresponding registry.
- Ministry of Health: information note on the approval of the Royal Decree regulating medical cannabis in Spain.