
Callum Armstrong
Superintendent Pharmacist & Independent Prescriber
Callum Armstrong is a GPhC-registered pharmacist and independent prescriber with over 8 years of clinical experience. Specialising in weight management, hair loss, erectile dysfunction, and dermatology, he combines clinical expertise with a background in digital health and pharmacy software to deliver evidence-based, patient-centred care. As Superintendent Pharmacist at Totiva Health, Callum oversees the clinical governance and quality standards that underpin every service.
8+
Years of experience
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Articles by Callum Armstrong
Maintaining Your Weight Loss with Mounjaro
Reached your goal weight with Mounjaro? Learn how to maintain your results long-term with flexible dosing options and lifestyle strategies that work.
Can You Take Mounjaro Every Two Weeks? Dosing Safety Explained
Stretching Mounjaro doses to every two weeks isn't recommended by medical professionals. Here's why the weekly schedule matters for safety and effectiveness.
What happens when you stop taking Mounjaro?
Your appetite returns gradually over 4-6 weeks, but most people keep significant weight loss long-term with the right maintenance strategies.
Peptides for Weight Loss: How GLP-1 Medications Work
GLP-1 peptides like semaglutide and tirzepatide can help you lose 15-20% of body weight by mimicking natural hormones that control appetite and blood sugar.
Glucomannan Powder: How to Use It Safely for Weight Support
Glucomannan powder can help you feel fuller for longer, but only if you use it correctly. Learn the proper dosage, timing, and safety tips from UK pharmacists.
When Does Mounjaro Start Suppressing Your Appetite?
Most people notice Mounjaro's appetite-suppressing effects within 1-2 weeks, but it can take longer to reach full effectiveness as your dose increases.
How to Store Mounjaro: Essential Storage Guidelines
Store Mounjaro pens correctly to maintain effectiveness. Refrigerate unused pens at 2-8°C or keep at room temperature for up to 30 days.
Mounjaro and pancreatitis risk: What to watch for
Pancreatitis affects less than 1% of Mounjaro users, but the symptoms can be serious. Learn the warning signs and when to seek help.
Mounjaro Needle Size: 4mm vs 6mm vs 8mm - Which is Best?
Confused about Mounjaro needle sizes? We explain why 4mm needles are recommended, how they compare to longer options, and tips for comfortable injections.
Mounjaro during pregnancy and breastfeeding - UK safety guidance
Current UK guidance on Mounjaro safety during pregnancy, planning conception, and breastfeeding - what the evidence shows and when to stop treatment.
Mounjaro Dizziness: Why It Happens and How to Manage It
Dizziness affects up to 1 in 10 Mounjaro users. Learn why it happens, how long it lasts, and proven ways to reduce your risk safely.
Does Mounjaro cause tiredness? Managing fatigue while taking tirzepatide
Up to one in ten people feel tired on Mounjaro. Learn why this happens, how long it lasts, and proven ways to boost your energy levels naturally.
Amycretin Weight Loss Pill: How It Works and When It's Coming
Novo Nordisk's promising new weight loss pill Amycretin targets two hunger hormones and shows impressive early results, but it won't be available until 2030.
Does Rybelsus Cause Yeast Infections?
Rybelsus doesn't directly cause yeast infections, but diabetes itself increases your risk. Learn how to spot symptoms and protect yourself while taking this medication.
Wegovy Costs in the UK: NHS vs Private Pricing Breakdown
Wegovy costs £100-300 monthly privately or £9.90 per prescription on NHS (where eligible). Find out exact costs and eligibility criteria.
Mounjaro UK Pricing: NHS vs Private Costs Compared
Mounjaro costs £150-250 monthly privately, but NHS availability varies. Compare your options and understand eligibility requirements.
How Long Does Mounjaro Stay in Your System?
Mounjaro takes around 5 weeks to completely leave your body after your last injection. Here's what affects elimination and when to expect it cleared.
Can You Eat Bananas While Taking Mounjaro?
There's no medical reason to avoid bananas on Mounjaro. We explain the myths around potassium, blood sugar, and GI side effects with this popular fruit.
Spotting Fake Online Pharmacies When Buying GLP-1 Medications
How to identify legitimate vs rogue pharmacies when buying Mounjaro, Ozempic, or Wegovy online. Essential safety checks before you order.
Flying with Mounjaro: UK Airport Rules and Safe Storage Tips
Everything you need to know about taking Mounjaro on flights - UK airport security rules, proper storage methods, and essential travel documentation.
Does Mounjaro Cause Lack of Motivation? Understanding Fatigue and Energy Loss
Many Mounjaro users report feeling less motivated or tired. Here's what causes it, how long it lasts, and practical ways to manage energy levels.
Ozempic vs Mounjaro vs Wegovy Costs in the UK: Price Comparison
Compare the real costs of Ozempic, Mounjaro and Wegovy in the UK. NHS availability, private prices and which offers the best value for weight loss.
Can You Buy Mounjaro Over the Counter in the UK?
No, Mounjaro cannot be bought over the counter in the UK - it's prescription-only. Here's where you can legally get this weight loss medication.
Mounjaro After Gallbladder Removal: Is It Safe?
Can you take Mounjaro after gallbladder surgery? Get clear medical guidance on safety, side effects, and what to expect from your prescription.
Can Mounjaro Affect Your Period? Understanding Menstrual Changes
Mounjaro can indirectly affect your periods through weight loss, especially if you have PCOS. Here's what to expect and when to seek medical advice.
Does Ozempic Raise Heart Rate? What You Should Know
Ozempic can cause modest heart rate increases in some patients. Learn about the cardiovascular effects, when to worry, and how to monitor safely.
Is Berberine a GLP-1 Receptor Agonist? The Science Explained
Berberine isn't a GLP-1 receptor agonist like semaglutide, but it does affect blood sugar and weight. Here's what the research actually shows.
Is Bass Safe to Eat? UK Guidelines on Mercury, Pregnancy, and Health Benefits
Bass is safe to eat when properly prepared, but pregnant women should limit intake to 2 portions per week due to mercury levels. Learn UK guidelines and benefits.
Ozempic and Heart Racing: Causes, Warning Signs and What to Do
Experiencing heart racing on Ozempic? Learn about the possible causes, when to seek urgent help, and how to manage cardiovascular symptoms safely.
Are DHT-Blocking Shampoos Worth Your Money?
Hair thickening shampoos promise to tackle male pattern baldness, but can washing your hair really stop hair loss? We examine the evidence behind DHT-blocking ingredients.
Male Hair Routine: Simple Care Steps for Every Hair Type
Discover the right hair care routine for your specific hair type, from daily washing schedules to product recommendations that actually work.
Hair Growth Cycle: Understanding the Three Phases and What Affects Them
Learn how your hair grows through anagen, catagen and telogen phases, plus what factors influence healthy growth and when hair loss becomes concerning.
Best Haircuts for Men with Thinning Hair: Expert-Recommended Styles
Discover the most flattering haircuts for thinning hair and receding hairlines, plus professional styling tips to maximise volume and confidence.
Clomid for Men: Off-Label Treatment for Low Testosterone and Infertility
Clomid isn't licensed for men in the UK, but some specialists prescribe it off-label for male fertility issues and low testosterone. Here's what works.
DHT: The Hair Loss Hormone Explained
DHT drives male pattern baldness by shrinking hair follicles. Learn how this hormone works, what blocks it, and which treatments actually work.
Can Women Take Viagra? Effects, Safety and Alternatives
Explore whether women can safely take Viagra, its effects on female physiology, and better alternatives for women's sexual health concerns.
Effects of Not Masturbating: The Science Behind NoFap Claims
NoFap and No Nut November promise amazing benefits from avoiding masturbation. But what does the actual scientific evidence say?
GLP-1 Patches for Weight Loss: Do They Actually Work?
GLP-1 patches claim to offer weight loss without injections, but there's no scientific evidence they work. Here's what you need to know about these unregulated products.
Enclomiphene for Low Testosterone: Alternative to TRT
Enclomiphene could offer a fertility-preserving alternative to testosterone replacement therapy, working by stimulating your body's natural hormone production.
Finasteride Side Effects: What Men Need to Know Before Starting Treatment
Sexual dysfunction affects 2-15% of men taking finasteride. Mental health side effects are rarer but more serious. Here's what UK research shows.
The Science Behind Why Beards Are So Attractive
From testosterone to evolutionary psychology, discover the fascinating research that explains why facial hair triggers such strong reactions in both men and women.
Blue Balls (Epididymal Hypertension): Causes, Symptoms & Treatment
Blue balls is a real medical condition called epididymal hypertension. Learn what causes testicular discomfort after arousal and how to treat it safely.
Retatrutide Dosage: Starting Doses and Schedules for Weight Loss
Learn about retatrutide starting doses, escalation schedules, and how this promising triple-hormone treatment compares to current weight loss medications.
How Diet Affects Testosterone Levels: Foods That Support Healthy Production
Discover which foods and nutrients naturally support testosterone production, from zinc-rich oysters to vitamin D sources and practical meal planning tips.
Does Coke Zero help with weight loss?
Exploring whether Coke Zero's zero calories translate to weight loss benefits, plus the surprising research on diet sodas and body weight.
Mounjaro Sulphur Burps: Causes, Duration and Effective Remedies
Experiencing egg-smelling burps on Mounjaro? Learn why they happen, how long they last, and proven ways to reduce them from dietary changes to OTC remedies.
How to dispose of your sharps bin safely in the UK
Using weight loss injections? Here's exactly where and how to dispose of your full sharps bin safely and legally in the UK, plus how to get a replacement.
How to Reduce DHT for Hair Loss: Medical vs Natural Options
DHT causes 90% of male hair loss. Finasteride blocks DHT production by 70%, while natural options like saw palmetto show limited evidence.
How Long Does Finasteride Take to Work for Hair Loss?
Most men see visible finasteride results within 3-6 months, with peak effects at 12 months. Here's what to expect from your treatment timeline.
How Long Does Minoxidil Take to Work? Your Timeline for Hair Regrowth
Minoxidil typically takes 8-12 weeks to show initial results, with noticeable improvements at 4-6 months. Here's what to expect month by month.
Finasteride vs Minoxidil for Hair Loss: Which Works Better?
Both treatments tackle male pattern baldness differently - finasteride blocks DHT production while minoxidil boosts blood flow to follicles.
How Long Does Cialis Last? Duration, Timing, and What to Expect
Cialis typically lasts up to 36 hours and starts working within 30 minutes to 2 hours. Learn about timing, effectiveness, and what affects duration.
How Long Does Viagra Last? Timing, Duration and What Affects It
Viagra typically lasts 2-3 hours but can work for up to 6 hours. Learn about timing, what affects how long it works, and how to get the best results.
How Often Can You Take Viagra and Sildenafil?
Wondering about Viagra frequency? You can take sildenafil daily if needed, but there are important safety limits to follow for maximum effectiveness.
How to boost testosterone levels: evidence-based methods that actually work
Low energy and declining muscle mass? Discover proven ways to increase testosterone through lifestyle changes, supplements, and medical treatments.
Foods That Can Help Boost Your Libido Naturally
Discover which foods contain compounds that support healthy blood flow, hormone levels, and sexual function - plus practical tips for your diet.
How to Take Viagra Safely and Effectively
Essential dos and don'ts for taking Viagra, including timing, dosage, and what to avoid for the best results and minimal side effects.
Does Minoxidil Work for Receding Hairlines? The Evidence
Minoxidil can help with receding hairlines, but there's a catch. We explain what works, what doesn't, and why timing matters for frontal hair loss.
Erectile Dysfunction in Your 50s: Causes and Treatments That Work
ED affects over half of men in their 50s. Understanding the physical and psychological causes - plus proven treatments - can restore your confidence.
Kamagra Oral Jelly: Safety Risks and Legal Alternatives in the UK
Kamagra Oral Jelly may seem like a cheap Viagra alternative, but it's unlicensed in the UK and carries serious safety risks. Here's what you need to know.
Does Viagra Keep You Hard After Ejaculation?
Viagra doesn't keep you hard after ejaculation, but it can shorten your recovery time. Learn what really happens and set realistic expectations.
Porn-Induced Erectile Dysfunction: Understanding PIED and Recovery Options
PIED affects growing numbers of young men. Learn the science behind porn-induced ED and evidence-based approaches to recovery and treatment.
Mounjaro Dosage Guide: From 2.5mg to 15mg Explained
Understand how Mounjaro doses increase from 2.5mg to 15mg over 16 weeks, which dose is most effective for weight loss, and what maintenance dosing involves.
Mounjaro timeline: when to expect weight loss results
Understand what happens each month on Mounjaro treatment, from initial side effects to significant weight loss over 18 months.
Where to buy retatrutide in the UK
Retatrutide isn't legally available in the UK yet, but social media sellers are exploiting loopholes. Here's what you need to know about safety and alternatives.
How Retatrutide Works: The Triple-Action Weight Loss Injection Explained
Retatrutide targets three hormone receptors simultaneously - GLP-1, GIP, and glucagon - potentially offering superior weight loss to current injections.
Mounjaro Golden Dose: Why the Fifth Dose Isn't Safe to Use
The leftover liquid in your Mounjaro pen after four doses isn't a bonus - it's a safety feature. Here's why using the 'golden dose' can be dangerous.
When to Take Magnesium: Morning or Night Timing for Better Results
The timing of your magnesium supplement matters less than consistency, but certain forms work better at specific times for sleep, energy, and digestion.
Weight Loss Injections: How Effective Are They for Long-Term Results?
Weight loss injections like Wegovy and Mounjaro help people lose 15-20% of body weight in clinical trials. Find out if they're right for you.
How Much Protein Is in an Egg? Complete Nutritional Breakdown
A large egg contains 6.3g of complete protein with all essential amino acids. Discover egg nutrition facts and how they fit into your daily protein needs.
Calories in Medjool dates: nutritional facts and weight management tips
Discover exactly how many calories are in Medjool dates, their nutritional benefits, and how they fit into a healthy weight management plan.
Switching Between Mounjaro and Wegovy: What Actually Happens
Thinking of switching weight loss medications? Here's what your doctor considers when moving between Mounjaro and Wegovy, including dosing and timelines.
Weight Loss Supplements That Actually Work: A UK Pharmacist's Guide
Discover which weight loss supplements have scientific backing and are regulated in the UK, plus what to avoid from a GPhC-registered pharmacist.
UK Weight Loss Diet Plan: Evidence-Based Meal Planning for Sustainable Results
Get a practical 7-day meal plan designed for UK dieters, plus shopping lists, prep tips, and evidence-based advice from registered pharmacists.
Does Finasteride Lower Testosterone? The Science Behind the Claims
Worried finasteride might tank your testosterone? The surprising answer involves a temporary rise followed by your body's clever balancing act.
How to Take Mounjaro at Home: A Patient Guide from Totiva Health
A pharmacist-led guide from Totiva Health explaining how Mounjaro works and how to inject it safely at home, with clear steps and safety advice.
How to Take Wegovy at Home: A Patient Guide from Totiva Health
Learn how to take Wegovy safely at home with this pharmacist-written guide from Totiva Health, covering injection steps, dosing, and safety advice.
