DoxycyclineDoxycycline Hyclate/Monohydrate

About Doxycycline

Doxycycline stops bacteria multiplying by blocking protein synthesis; like other antibiotics, it does not treat viral infections such as the common cold. Its labels cover Rocky Mountain spotted fever and other rickettsial infections, chlamydia and some other sexually transmitted infections, some respiratory infections, plague, tularemia, cholera, anthrax, syphilis and other infections when penicillin cannot be used, and, as adjuncts, intestinal amebiasis and severe acne. Adults usually take 200 mg on the first day, then 100 mg a day; children are dosed by weight. To prevent falciparum malaria in travelers staying under 4 months, adults take 100 mg a day from 1 or 2 days before travel until 4 weeks after leaving the malarious area. Lyme disease is not on the current labels cited here (LymePak, approved in 2018 for early Lyme disease, is discontinued), and preventing it with doxycycline after a tick bite is not an FDA-approved use.

There is no boxed warning, and anyone allergic to a tetracycline must not take it. The labels say that tetracycline-class drugs used during tooth development (last half of pregnancy, infancy and childhood to the age of 8 years) may cause permanent discoloration of the teeth (yellow-gray-brown), more often with long-term use but also after repeated short courses, and that enamel hypoplasia has been reported. They say to use doxycycline in pediatric patients 8 years of age or less only when the potential benefits are expected to outweigh the risks in severe or life-threatening conditions (e.g., anthrax, Rocky Mountain spotted fever), particularly when there are no alternative therapies. Exaggerated sunburn can occur, so excessive sunlight and artificial ultraviolet light are avoided, and treatment stops at the first skin redness. Other risks include Clostridioides difficile diarrhea, irritation and ulcers of the esophagus, and intracranial hypertension (raised pressure around the brain), more likely in women of childbearing age who are overweight or have had it before. Side effects include nausea, vomiting, diarrhea and loss of appetite.

MedlinePlus warns that doxycycline can harm a fetus, and breastfeeding advice differs by label. Oracea is labeled only for the papules and pustules of rosacea in adults. Its label says it is not bioequivalent to other doxycycline products and is not for bacterial infections; it is not used in children under 8 or in the second and third trimesters of pregnancy, and breastfeeding is not recommended until 5 days after the last dose. Doryx MPC and some generic delayed-release tablets are labeled as not substitutable milligram for milligram with other oral doxycyclines. The labels also say doxycycline may make birth control pills less effective.

Taking Doxycycline

How to take it

With a full glass of water, to protect the esophagus; take it with food or milk if it upsets your stomach. Do not chew or crush delayed-release tablets; some can be broken up and the pellets sprinkled on a spoonful of applesauce. Take Oracea once in the morning on an empty stomach, preferably at least an hour before or two hours after a meal. Finish the course even if you feel well.

If you miss a dose

Take it as soon as you remember, unless it is almost time for the next dose; then skip the missed dose and carry on as usual. Do not take a double dose.

Storage

At room temperature in a tightly closed container, away from light, excess heat and moisture, out of reach of children. Mixed suspension keeps two weeks at room temperature; then throw away what is left.

Interactions to know about

Antacids with aluminum, calcium or magnesium, iron and bismuth subsalicylate reduce its absorption; MedlinePlus says to take iron 3 hours before or 2 hours after it. Blood thinner doses may need lowering; barbiturates, carbamazepine and phenytoin shorten its action; it is avoided with penicillin and isotretinoin; and methoxyflurane with tetracyclines has caused fatal kidney damage.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Doxycycline differs from pharmacy to pharmacy

Hyclate tablets rated to Acticlate and monohydrate capsules rated to Monodox come from several makers, while some strengths, such as the 150 mg monohydrate capsule, have few. Generics are rated equivalent only within the same salt, form and strength, so a pharmacist does not swap hyclate for monohydrate, or a tablet for a capsule, without the prescriber.

Ways to pay less for Doxycycline without insurance

• Ask the prescriber whether hyclate and monohydrate would both suit you, since a pharmacist cannot switch salts alone.
• If Oracea or a delayed-release tablet is prescribed, ask whether a rated generic exists for it, and check that the prescription allows substitution.
• For malaria prevention or acne, ask for a prescription covering the whole course.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Doxycycline

1. 1.Is my prescription for hyclate or monohydrate, and which form?
2. 2.How far apart should I take it from antacids, calcium or iron?
3. 3.How should I protect my skin from the sun while I take it?
4. 4.Does it interact with my birth control, blood thinner or acne medicine?

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