Pharmacy Expert Issues Critical Warning on Over-the-Counter Sleeping Aids
A senior pharmaceutical expert has issued a stark new alert regarding the potential dangers of commonly used sleeping pills, specifically highlighting the risks associated with promethazine and diphenhydramine. Dipa Kamdar, Senior Lecturer in Pharmacy Practice at Kingston University, emphasised that these medications, widely available without prescription, can lead to serious harm, including dependence, tolerance, and even life-threatening side effects.
Misconceptions About Over-the-Counter Safety
In a detailed article published on The Conversation website, Kamdar addressed a widespread public misconception. "Many people assume that medicines sold over the counter are inherently safe. After all, if you can buy something in a supermarket or high street pharmacy, how dangerous can it really be?" she noted. However, she clarified that the reality is far more complex, with several commonly used non-prescription drugs carrying genuine risks when misused.
Kamdar explained that these risks become particularly pronounced when medications are taken in higher than recommended doses, for extended periods beyond their intended short-term use, or for incorrect purposes. The assumption of safety, she argued, often leads to complacency among consumers, potentially resulting in adverse health outcomes.
Specific Risks of Promethazine and Diphenhydramine
The expert focused her warning on two specific sedating antihistamines frequently marketed as short-term sleep aids:
- Promethazine: This medication can rapidly lead to tolerance, meaning users require increasingly higher doses to achieve the same sedative effect. Long-term users have reported severe rebound insomnia when attempting to discontinue use. Alarmingly, promethazine is also used recreationally in mixtures like "purple drank," a combination with cough syrup and soft drinks that can cause extreme sedation, slowed breathing, and significant harm.
- Diphenhydramine: Similarly, this antihistamine poses risks when used improperly as a sleep aid, with potential side effects including confusion, dizziness, and cardiovascular issues.
Kamdar pointed to recent research that has linked sedating antihistamines to a rising number of deaths, prompting calls for a thorough review of how these substances are supplied to the public. Both drugs are strong sedatives, and NHS guidance explicitly advises against taking them together due to the heightened risk of excessive sleepiness, severe sedation, and side effects like confusion and dizziness.
Official NHS Guidance and Side Effects
The NHS provides clear warnings about the serious side effects associated with these medications. For promethazine, individuals are advised to contact a doctor or call 111 immediately if they experience:
- Confusion or muddled thoughts
- Blurred vision
- Difficulty urinating
- Yellowing of the skin or eyes (a potential sign of liver problems)
- Unusual bruising or bleeding
- Muscle stiffness, shaking, or abnormal movements
- Fast, pounding, or irregular heartbeat
- In children, aggression, hallucinations, or hyperactivity
For diphenhydramine, the NHS recommends immediate medical attention if users develop:
- Fast or irregular heartbeat
- Numbness or pins and needles
- Extreme restlessness
- Confusion or an inability to concentrate clearly
Kamdar's warning underscores the critical need for public awareness regarding the potential hazards of these accessible medications. While they serve legitimate purposes for allergies and short-term insomnia, their misuse or prolonged use can lead to significant health complications, reinforcing the importance of adhering strictly to recommended guidelines and consulting healthcare professionals when in doubt.
